I hear you're under alot of pressure.

Are you on medication? I had something happen to me that was devastating a fews years ago, but since I have 2 young girls, I wasn't able to fall apart, even though I felt like crumbling. To be honest I went into what I call - robot mode - I just did what needed to be done.
I understand you're grieving and feel lonely but the priority is school for you - you need to graduate. Since you have a job can you help out your parents financially?? This is a transition time and it's normal to feel pressure. How's your diet and exercise? Other people will come into your life, so don't worry about that for now and it's normal to grieve that relationship. Don't worry about the past and focus on the present -keeping yourself well and finishing school -schools your future. You say you're struggling with your sexuality - maybe you should post in the sexuality forum. Speak to your doctor if you can't cope.