How do I bounce back?

I'm failing at being a Mum.

Yeah, there's the imperfect Mum... And then there's me.
This is going to be a long one so please bear with me.

My 15yr old and 6yr old Sons live with me. My 11 and 12yr olds boys live with their Dad (their choice).
My 12 yr old was diagnosed ADHD 12 months ago after I convinced their Dad that we needed to take him to see a Paediatrician after the many fights he had been getting into at school.
To be fair, his Dad had taken him Psychologists and counselling over the years convinced it was a trauma response from when I had Post natal depression which turned to Postkpartum psychosis when he was a baby.
The meds he's been on since seeing the Paed has helped him immensely. Where he was not able to do any work and was extremely disruptive in class, he now completes all of his tasks and no longer gets into fights at school. However, he is still abusive to his 11 yr old brother and mimics his father's behaviours similar to that of Narcissistic personality disorder (this has been confirmed by a Psychologist, and a behaviour specialist that was working with our family has also labelled their Dad as a misogynist). Scarily, their Dad is due to graduate from his Psychology degree early next year.

Fast forward to the last few months. My 6yr old has been inflicting self harm and has been having massive meltdown. This started after school returned after lockdown. It continued with him telling me everyday he wanted to die, to kill himself, and hates his life. He would find sissors or knives and hold them against his neck with such conviction and anger that I was terrified he was going to hurt himself. Anything potentially dangerous ended up being packed away and hidden but then he resorts to punching himself in the head, ripping his clothes, pulling his hair, or smashing things such as his Xbox controller or his toys.
This of course led us to the emergency department at The Children's Hospital for a mental health assessment with a Psychiatrist. They told me to take him to see a Psychologist and Paediatrician.
Long story short, the Paed has diagnosed him with ADHD with Autistic traits and the Psychologist has told me after 6 sessions that there is nothing more that she can do for us and has referred us to a place that does neurofeedback. I took it upon myself to take him to get a speech assessment done as I felt there was more to this whole thing. It turns out he is in the 1% of children his age that has a severe language and 'something' delay. I can't remember what it was but it's significant. I think I tuned out because I'm starting to not be able to cope.

His Dad (the narcissistic one) has very little to do with him and there is no support from him whatsoever. We separated 6 years ago and we don't have the best relationship. My 6yr old doesn't like to go visit him and I don't force him to go (this is based on advice from his Psychologist). This has taken a huge hit to his Dad's ego and now I receive passive aggressive text messages from him because of it.

A few weeks ago my 15 yr old was hit by a car on his way home from school. It ended up with him in an ambulance to the hospital. Thankfully he was ok except for a nasty concussion and lots of bruises and grazes.

Fast forward again to last week, my 11 yr old was staying with me for the weekend and my 12 yr old chose to stay with his Dad for the weekend. During that time, my 12 yr old was speaking to my 11 yr old on the phone and I overheard my 12 yr old belittling my 11 yr old. I told my son who was with me that he doesn't have to put up with that as he doesn't deserve to be spoken to like that. No one does. To which he replied that he always speaks to him like that. So I told him to hang the phone up and not to tolerate that kind of behaviour. Almost immediately after my 11 yr old hung the phone up, my 12 yr old sent me a text message that I was a disgrace "🤮🤮".

I'm getting tired. My soul is getting tired.

I received my 15 yr old Sons school report yesterday. He failed 7 out of 9 of his subjects!
How did I miss this!!! I didn't even know he was struggling so badly! The school has never communicated to me that he was going to fail year 9! My Son has never mentioned the struggles he was facing. How did I miss this????
Completely shattered, I approached him and told him not to worry about his report. This year has been a covid year and pretty sh#t year for everyone and that we are writing this year off! He thanked me and we haven't spoken of it again but he did ask me what his options were leading into year 10. We spoke about apprenticeships and options for his HSC. Told him to pursue what he loved or was passionate about.

I can feel myself slipping. I'm becoming irritable. I'm feeling disconnected with my friendship circles. I'm drowning myself in my social work studies and caving in to drinking alcohol to cope. My house is starting to look like what I feel inside.

I'm tired. My soul is tired. And I fantasize about doing things to end my life because it's so hard. And I have no real support. No one who truly knows what's going on in my head. They all have their own sh#i happening.

Anyway, thanks for being here for me. Especially if you lasted this long into my novel.