Depression And Anxiety. What Should I Do?

I’m 17, and up until half way through year 10, I was an A grade student. I’d always been shy and when my grades began to fall, I began to feel even worse. I met my boyrfriend, and he helped me alot, but i’ll come back to that. At the end of 2008, I got Glandular fever and I became very isolated from my friends and lost alot of them, and I became very dependent on my boyfriend because of that. Since being sick, I developed Social Anxiety Disorder and Mild depression. it stayed like this for about two years.
Since June this year, I’ve lost even more friends and I’ve been dumped by my boyfriend because he ‘couldn’t deal with me anymore’, my parents are getting a divorce, and I feel completely pointless in the world now. My entire relationship with my boyfriend, which I didn’t realise at the time, was emotionally abusive. He belittled me in front of my friends and called me stupid all the time because I was getting better marks than him. He hit me a few times, but I thought nothing of it. My relationship with him has taken away all my self esteem and worth I had for myself.
I am in counselling, but I don’t find it helps. I usually cry myself to sleep and think about harming myself and I don’t know if those thoughts are serious or not. I struggle to be in a group situation, and I feel invisible to everyone I used to have. I don’t know what I can do for myself anymore, because I feel like I’m just wasting everyone elses time.
Can anyone give me any advice or something?