Please, talk to your GP. He / she can prescribe you anti-depressants or recommend you to a specialist.
And don't worry - your friends haven't abandoned you. Get in contact with them, and talk to one of them about it. Arrange meets with them, even if it is just shopping or watching a DVD. They are still your friends, even if you haven't seen them in a while. Remember, you have a lot to live for. You have a boyfriend - talk to him about your situation, and he will reassure you. If you're worrying about uni, find someone you can talk to, such as a member of staff. Sorry I can't give anymore detail - I'm still at school.
And please, don't apologise for the post. We're here to help.