Without the requested information, I can only provide you with the following general response, which will hopefully still answer your query. First of all, I am sorry to hear about the issues you have experienced in your situation.
As far as the dismissal is concerned, the main issue in the circumstances is the fact that you have only been continuously employed at you place of work for less than 2 years. That means that your employment rights will, unfortunately, be somewhat limited. Most importantly, you will not have legal protection against unfair dismissal. This basically means that your employer can dismiss you for more or less any reason, and without following a fair procedure, as long as the decision is not based on a reason which makes a dismissal automatically unfair. They can proceed with a dismissal even if you had done nothing wrong and also without following any specific fair procedure or proving that any of the allegations are true.
As mentioned, there are some exceptions to this, in which case the 2-year rule does not apply. These include situations where the dismissal was wholly, or partly, due to:
- Discrimination due to a protected characteristic (i.e. because of gender, race, religion, age, disability, sexual orientation, etc.)
- Taking, or trying to take, leave for family reasons including pregnancy, maternity/paternity leave, parental leave, adoption leave or leave for dependants
- Raising concerns about health and safety or other unlawful acts by the employer and being penalised as a result by being dismissed
However, if the dismissal had nothing to do with any of the above exceptions, you would not be able to challenge it due to not meeting the minimum service criteria for claiming in the Employment Tribunal. In that case your only protection would be if you were dismissed in breach of contract. That would usually happen if you were not paid any contractual notice period due to you, unless you were dismissed for gross misconduct. That is where you were guilty of something very serious which justifies immediate dismissal, without any notice pay.
In any other circumstances, you would be due a minimum notice period, as per your contract and associated pay. If you did not have a written contract in place you would be entitled to the minimum statutory notice period of 1 week. The employer would either have to allow you to work that notice period and pay you as normal, or they can decide to pay you in lieu of notice. That is when you are paid for the equivalent of the notice period but your employment is terminated immediately and you are not expected to work through your notice period.
As to the meeting, you do not have to attend it and it is entirely up to you whether you do so. There is not much more the employer can do now that you have left, but if you want your voice heard then you could still take part and see what they say.