1) OP, dont EVER let anyone tell you that because you take antidepressants you are not strong enough, or anything like that. Realizing you are having a hard time, and taking care of it is BRAVE, and it absolutely has NO CORRELATION to you being a successful doctor. If anything i can see how it might make you more empathetic to your patients.
2) I moved across the world from my family, and i know how hard it is. It is heartbreaking. I can definitely say that my relationships with my family actually improved since i moved: consider starting a whatsapp chat with your family, schedule regular video chats, share a lot of pictures with them, give them a virtual tour of your medical school, etc. Plus you will have holidays, vacations, etc. It is better than you think. Plus you can schedule away rotations in your home town, and you can find research opportunities there (you can even already start working on finding places for research next summer). I think all of these things might help you look forward to good things. What do you think?
3) also, - everyone has different triggers and things that upset them. For example, i have no problem working with the dead, i counselled criminals (including violent crimes), i worked with rapist, etc. But show me a dead animal and i will probably want to cry. Everyone is different. Never assume that because OP is sensitive about leaving home, he/she wont be an absolute hardcore badass is other aspects of medicine. assuming that is, honestly, kind of shows lack of knowledge about human psyche and lack of life experience.
Bottom line: OP, your feelings are justified. Things will definitely get better when you get to medical school (the white coat ceremony, scrubs, all that is actually very exciting and will definitely inspire you
. Just keep going, maybe listen to some pod casts on these issues, meditate, try to stay afloat.