Hello,
Understandably, you have been facing these relationship issues for sometime now as your description. Howsoever, as the two of you are still together, it means that the person fulfils some emotional needs which keep you going. If such is the case, you will need to sit back and review at what expense you are willing to continue with the relationship.
In case you decide to carry on, I would suggest that you consult a psychotherapist or psychiatrist to communicate clearly and explicitly to your boyfriend about your needs and boundary setting.
In case you decide not to, communicate clearly, firmly to your boyfriend and move on seeking support from friends, family and if required a therapist.
Next Steps
As of now, just before your exams, focus on yourself. eat well, sleep well and stay close to friends. DO NOT take any words said by him personally. try not to analyse his words and actions too deeply. if it doesn't help much, seek professional help. good luck!