Mental Health and Suicidal

My daughters father is battling deep depression and mental health issues. We are not together and he has broken my heart so many time but I try my best to co parent. I finally moved on and put my foot down I am in my healing stage and just want to be FREE. But lately it’s been at its worse. He goes MIA and blocks everyone. It’s hard to get in contact with him. After he feel like he’s doing ok, he comes back around like it’s nothing. But then the cycle repeats. I use to extend my hand, chase him and speak positively in him. But now I am at my ends, I’m tired. I’m raising our child alone and I can’t be there for him like he wants me to. I feel bad for walking away because I too suffer from depression and anxiety and know how it feels. But I always get help and take my meds. He doesn’t want to get help or do anything. I’m just scared I will get a call one day that he took his life as he has been writing me messages as if that’s what he will do. But I also feel like he guilt trips me. Idk what to do. ADVICE PLEASE.