I don't know what to do I don't think I can fight this again. Why does it keep coming back?

welll I am almost 17 and have been struggling with severe depression, self harm, anxiety and behavioural/emotional problems from the age of 13. up until 6 months ago I was at the point where Inpatient intervention was needed. I started smoking pot which helped balance out the highs and low's which I got a lot of, if I was on a high I'd be constantly babbling, running around, making weird noises, couldn't concentrate and making split second decisions..people couldn't stand to be around me when I was like that although I wasn't that fun when I was suicidal either. My moods Balanced out for like 3 months but now I'm back to feeling my depressed anxious self. I'm not currently taking meds I used to take fluoxetine but that made my moodswings worse. I'm plagued with thoughts to self harm everyday like I used to (nearly all my cuts needed stitches) and Im getting suicidal thoughts, making plans etc.. because its summer im getting less support than usual from CAMHS and they're set to discharge me from their services at the end of August because they say I'm better. why am I not fixed. Ive done art therapy, two kinds of talking therapy and I see a psychologist. (yes I had therapy 4 times a week) I honestly Don't think I can do this again especially as I'm starting college in september which is a big thing as I left school due to anxiety 2 years early.

help, I really don't know what to do.