Well, first and foremost, your therapist is extremely unprofessional and not a good one by any means. That said, there are some amazing mental health professionals out there. I know it's scary and hard but I would definitely not let the previous one deter you from finding a good therapist. I would personally look for an experienced psychologist and make a list of questions to gauge if they're the right fit for you and their approach (different psychologists and therapists utilize different approaches). If you go to the first appointment and they just don't mesh with you, don't be scared to go on to look for the next one until you find one that fits or ask to talk on the phone first to get an idea.
As for what helps me...
Ultimately, I was in an abusive toxic situation so mostly getting out of that environment was beneficial for my mental health. Likewise, making changes to my environment and doing things I deserved to do but didn't know I deserved or could do was helpful. So, asking what you want and then putting together how you're going to make that a reality or what you need to go for those things. Also realize that that's something great to do with the professional you work with once you find someone great. Recognizing that you are worthy, amazing, and can achieve what you want for your idea of happiness.
Most of all, not trying to preach to you (but since you asked and it helped me the most), Buddhism helped me. Learning that nothing is permanent, learning about the concept of suffering, learning about responsibility of suffering, learning about attachment, learning how to live now and not the past or the future...etc...All those huge themes in Buddhism and the teachings were extremely healing for me. Talking to a professional to examine and understand the things I went through and doing research on my own on those things as well were helpful.
Now...this is going to sound bad...but..
My suicidal thoughts are always there especially as a suicide survivor. Having attempted suicide, suicide isn't really something that ever leaves for me (at least not thus far). Life can be perfect and somewhere in part of my day it is there. It's hard to explain why that is or what it means for me and I think it's really only something someone that has suicidal thoughts or attempted suicide understands. It's not even necessarily a negative in a way or something that bothers me personally. In a weird way it's almost like a comforting thing. In any case, all I know is that it doesn't control the state of where I am now, where I will be, or how I feel for life/future...it's there and I acknowledge it for what it is but then I still do the things I want in life, look to the things I want, make the changes that make me happy, love the people I love, love myself, and so forth.
Of course, we're all different and what you are experiencing is certainly going to be different and your journey is going to require potentially different things. That's okay and that's what makes having a great psychologist so beneficial in terms of working together to get to the root of things you're dealing with and to examine what to do.
Right now, I would really suggest lots of self care in the meantime until you find someone you trust. I know it may be hard especially if you feel so low in self worth. However, try to do things that build you up. Try to get out to places to treat yourself, try to do activities that give you release (swimming is one for me...for some, yoga..or running...etc), try to write yourself letters contradicting the negative perceptions you have for yourself, try to get out and experience the things that, for you, make life worth it. If you ever wanna talk, feel free to message me anytime.
Also, I'm really sorry to hear about your mother and that you were in hospital. I hope your mother and you are making good recoveries and I'm keeping you both in my thoughts.