Improving sex life

Does anyone have any tips on improving mine and my boyfriend’s sex life?

Context: We are mid distance (both studying for our postgrad degrees in different cities, but we try to see each other during the weekends , or every other week). He has recently started taking sertraline, which is making it harder for him to get in the mood and then to finish. Despite us talking about fore play, I feel we still have room to improve, I just don’t know how. Years ago I was told I have vaginismus, so at the beginning of our relationship everything was painful for me. Years on, I’m much better - but still when everything moves too quick it hurts and I don’t feel mentally there. To be honest, I rarely finish with him which upsets him because he then gets insecure. I don’t know how to improve it, I’ve heard about lots of ideas but I also don’t know how to bring up new ideas without making him feel like I’m unhappy with our sex life. He definitely brings up these things less than me, and I don’t want to pose the situation as me being unsatisfied. I’m finding it tricky to navigate, with his medication changes and less time spent together and us not really being kinky so role play etc isn’t appealing, I’m not sure what else we can try. Any tips and ideas would be much appreciated, and if anyone has had experience with libido changes in their partner when they’re on medication that would be great to. Thank you ladies