I am very sorry to know about this very frustrating and painful situation.
It seems it could have become overwhelming for you to find yourself in this dilemma.
It is a sad and challenging situation, and I think you reacted the way you do because of how things changed in your long term relationship.
I think you got attached to your ex-boyfriend and your life together, all what you invested in it, emotionally, mentally, physically and financially too. You were life partners, but he became this neglectful partner for the past 1+ years, literally using and abusing your love and trust, which was totally incompatible with a mature and healthy relationships, making of your life together something painful and very frustrating for you.
That's why I think the attention, affection, respect and "reciprocity" this coworker offered to you was so appealing, and led you to leave your ex-boyfriend.
Right, that's what I was thinking and commenting about it. I think you need first to take enough time to process what happened with your ex-partner, for you to be able to truly get into this new relationship without feeling confused or conflicted.
I think things happened too fast.
What do you feel towards your ex-partner and how did he react when you decided to leave?
Then he was never able nor willing to truly acknowledge all those serious issues he created, leading to abuse and neglect, nor to take full responsibility for them and commit to work on making real and effective changes, right?
I see! Then It does make sense why you felt that way and why you allowed yourself to be open to explore things with your co-worker.
Then I do truly believe that your impulses to get back to your ex-partner are mostly based on attachment, and the love you built for so long, but one that was not reciprocated, that turned abusive and neglectful, manipulative and painful.
While nobody know how this new relationship would evolve in the long run, what you know is that it's been working fine so far, and if both of you allow yourselves to work on building it, without allowing any form of neglect, abuse or disrespect to undermine it, then your chances to make it work in the long run are very high.
I think if after 4 years in a relationship a person becomes the way he did, regardless the pain he caused to you and the attempts you made to work on it, to heal it and make it work again, and perpetuates that pattern for 1-2 years, then I would not feel optimistic about it, and believe it would be unrealistic to expect significant changes, since he has not shown real caring nor even respect towards you for that long.
I think you have the right, need and responsibility to build a fully and whole healthy, mature, happy and fulfilled relationship and reality, where you happen to be truly reciprocal, without any form of neglect or abuse undermining it. Both are equally responsible to make that happen, that's the only way relationships could truly work.
So there is nothing stupid or irrational in your expectation and decision to build this reality with a person who objectively shows capacity and willingness to responsibly work on it with you as life partners.
Please feel free to contact me if you have any further questions and to follow up, since I am here willing to support you as possible.
You can contact me using this direct link to my profile http://www.justanswer.com/relationship/expert-rafael-morales-toia/, just make sure you state "For Rafael only" in your request, for other experts to know you want me to reply, and I will respond in less than an hour most of the time.
Thank you for your trust. Take gentle care and consistent action.
I can see how tough it has become for you, but only you know how it feels, and that's why you need to carefully assess the pros and cons of each option, and not to push yourself into anything without making sure first you have a clearer mind about what you really want and are willing to afford now and for the long run, based on your concrete experiences.
Individual psychotherapy could be the best source of professional support for you to work on yourself around this tough situation, so you could make sure you would not self-sabotage nor expose to any form of neglect, abuse or manipulation.
Rushing into the new relationship did not help, but I believe you were already waiting for too long, tolerating the neglect and abuse from your partner, and you needed and deserved much better, and that's why you felt to attracted to your co-worker, it was very appealing to you because he offered those key things that your long term partner refused to share with you regardless your efforts to work on it. In your message you described how he was dishonest, manipulative and never consistent with his actions, and all of that show how poor and unhealthy his love became.
Now there is no way to change the past, you need to focus on reality, the present moment, and see how worthy it is for you to give your ex-partner another chance while knowing you worked on that for 1+ years without any significant improvement.
You also need to be very aware of how much you are willing to afford leaving this other person who has been very good towards you go away from your life. I think that if he really cares about you as he has shown to the present, he would be understanding and supportive not pushing you, but you would have to work on yourself if necessary with profesisonal support, so you would not self-sabotage.
Some times it can but only if it was an isolated incident and not a chronic issue or multiple times, and only if the person's "actions" rather than his words do clearly show you he respects you, cares about you, and makes his best o deserve back your trust and affection, otherwise it would be self-sabotaging to offer a new chance to a person presenting such behavior.
I think a person should only stay in a relationship if it is truly healthy and mutually fulfilling, otherwise it would become empty, codependent, and unable to offer any real happiness nor joy and grow in life at core levels, even when at other areas it could be beneficial. I also believe that if the relationship is not only non fulfilling but neglectful, abusive, manipulative because of a partner's chronic unacceptable behavior, it would be self-sabotaging to attach to it , perpetuating it because of how many years the person has already spent with such person. It would be like justifying present abuse, neglect and suffering, and perpetuating it because of having spent years together, like if time itself could justify present and future neglect and abuse.
But each person has her own value and belief system, and no matter how much we could not agree with them, each person has the right to choose what they want, and there are many people who choose to perpetuate dysfunctional relationships or marriages because of property, children, society, families, finances and other reason. Obviously priorities could be very different, but all will have to afford the consequences of their choices, and no matter how bad they may feel about them, as long as they fuel them, their reality will not change. so it is very important to be clear and truthful with yourself about your core needs and expectations, and what you want or not to afford.
It could be very tricky because you a person with codependency problems could very easily self-sabotage, then it is important to take into account realistic factors in place, core feelings, concrete experience you had with each person, and then, from sound reason and healthy feelings choose who truly deserves and is willing to share with you and work on building something really healthy, reciprocal and fulfilling.
Then if your feelings are not codependent but guided by good, realistic insight, they would be wise and lead t you in the right direction.
That's why I suggest counseling or psychotherapy.
Then do not push yourself and work on yourself first, then you would know what is the best for you.
There are many professional online directories for you to review and get in contact with those that you'd like to talk about it. Let me provide the direct links.
There you have to review many professionals with their acreditations, experience, approach and more.
You're very welcome.