How does your school not have a 1 year leave of absence policy? One of my classmates had a kid at the end of her first year, so she took a year off and now she just joined back into our class for year 2. Our school doesn't allow more than 1 year though, iirc. So if she had to repeat a year, or already took a year off, they would maybe excuse her. Anyway, that really sucks. As an absolute worst case scenario, can she transfer to a carribean school? Or one of the for-profit non-stateside schools? Has she taken step1 and/or step2s yet? I don't even know if you are in a US allopathic school with the same rules, but hopefully she gets something figured out. Because that really sucks.
As far as your HIV+ friend, I can't imagine being in his shoes. It isn't a death sentence like it was 30 years ago, but it still really sucks. His quality of life is going to diminish and his life expectancy is probably plummeting (esp with his self-destructive behaviors). I just had a friend who was diagnosed with DM1 (he was in full blown DKA during one of our finals and didn't know it until later that night when he went to the ER and found his random BS to be 1700+), and even though he is managing it super well, his life expectancy just got cut by a decade. It just would really suck to find out you have a disease like that. You never expect anything that big/bad to happen in your life. Anyway, I think the last thing he wants to hear is that he will be fine. Sit down and listen/agree with him that his situation sucks. But then say, but it will suck even more if you keep acting like this. You got dealt a bad hand, but you can't just give up.
tl;dr life can suck. Let's just get plastered from eating too many gross cheap tacos.