Hi, I hope I can offer some assistance.
This is a very difficult situation for you. With trust being one of the cornerstone's of a healthy relationship, without having an appropriate level of mutual trust, and being able to respect the privacy and boundaries of each partner, the relationship, as you have mentioned, can become prone to some negative, controlling and toxic behaviours as they are introduced into the relationship.
I have attached a link for relate, which might be a first step, and you can contact them yourself even if your girlfriend isn't willing to come along at this stage.
It sounds as though your girlfriend experiences some insecurity around the relationship, and this might be in relation to relationships in general. Without acknowledging and addressing these issues for you both in a healthy, mature and productive way the inappropriate behaviours you have described risk escalating, and further damaging and eroding the positive aspects of the relationship, as well as further isolating you from your friends, family and affecting your career. I hope you are ale to find the support you require.
Do let me know if I can offer any further assistance.
*If you are happy with my response, your positive rating at this time would be much appreciated.