Distressed mum

Last Christmas I found out my son has been self- harming and had made a half attempted suicide attempt - this completely shocked and rocked my world. We quickly went to the Gp and got into the CAMHS system but my son wasn’t open to the sessions and did 6 but the therapist said she couldn’t force him so we came out of the system. We have been monitoring him and thought it was all under control. Until school called last week to say my son is self harming again and has made another sucide attempt with some of my husbands medication and he is finding it hard controlling the harming and has suicide tendencies much more often. I just can believe we thought he was coping ok. He told the school he has been keeping it quite to protect me but I am now besides my self with worry. We went to the GP that day and ended up in AE and are now awaiting CAMHS- but I just don’t know how to support him - I don’t want him to feel the stress of my anxiety and am trying my best to be as strong as I can. The anxiety last Christmas of worrying every time I opened my sons door to what I might find has returned. We ask him what is it that is making him self harm and make him think about suicide and he just says he doesn’t know. How can you help a problem when you don’t know where it stems from? We are 9 months in from first finding out and I feel that we have let it get worse.... I am taking all elements out of the house that he could use to harm and will await to See how CAMHS can help. I’m just lost...