Oh god, I have just read your last comment, OP. "My Nan commit suicide about 18months ago and I was the last person she tried to contact before she did."
I am so, so sorry this happened to you. No wonder you feel so bad. You are a kind and loving person and you feel guilty for things that aren't your fault.
You are not in the least guilty, and I'm sure it's the last thing your poor Nan would have wanted you to feel. But that was a traumatic shock for you. I'm trying to control my anger at your CF partner for being such a bloody burden on you, when you need some love and support.
OP, I never talk about this, but I wasted several years of my life with a man I never intended to live with. He told me early on that he had made a couple of suicide attempts in the past when relationships had broken down.
He was very difficult and demanding, but also very needy. He always broke down when I tried to end the relationship, and I always gave in. This went on for several miserable years, till I had a life-threatening illness and suddenly thought If I survive, I'm not going to live like this any more!
I ended the relationship, survived the illness, he didn't kill himself and I have never looked back.
OP, he wasn't my responsibility. Your partner isn't your responsibility. Your children and your health are your responsibility.
I hope you are able to do whatever you need to protect yourself and your children. You have given so much to this man, who will go on taking till you are completely worn out. Please be kind to yourself now.
Sending you love and sympathy.