I'm sorry to hear about your troubles.
Everyone reacts to such things differently. As much as I know that you may not like this, your only real option is to just carry on with life and grin and bare it. Of course it's not something anyone would want to here, but there is no other alternative in life other than to do just that. Just hang in there
Concentrate on your school work and exams as it is extremely important. Talking to your parents again and getting your thoughts and feelings hear sounds like a good idea if you feel you need it again.
As Aylaine said, people come and go in life, whether they are simply acquaintances or loved ones.
You have to take the good with the bad my friend. Everyone has felt like this at sometime or another, and their existence proves that there is a way to get over what you are feeling (if you can understand that). Take care <3
My apologies if I haven't made myself understood. I am extremely tired.
If you want to talk or anything like that, feel free to PM me
I'll give you a run down of my situation:
My father is going deaf, my brother has learning difficulties and ADHD and my mother had a stroke last Novemember (whilst I was at university). She is currently undergoing various therapies to improve her current condition.
I'm still in the aftermath of a depression (I'm not depressed, but I just can't sleep properly and haven't done for 3 years now).
I've been having trouble applying for a new university course and securing funding for it (I was going to enroll in September, however due to being messed around by the university I now have to wait until January 2011 to enroll whilst my friends have already gone back.
And that's only a fraction of the stuff I have to deal with (I won't bore you or anyone else with the details - no one really gives a shit - I wouldn't either

)
Like I said in my original point. You are not alone. Huggles!