Laurie, nothing you've really said so far I haven't done myself... including mental breakdown and being arrested. Been there, done it, all during when PTSD was uncontrolled, when my life was falling apart and I had no idea what the f*ck was wrong, why, or what I could do to stop it all.
It does get better though, and you will move beyond it, trust me on that. Yes, it will take time... for me, some years actually, but I come out the other side and with persistence and perseverance, so will you. Don't fight the grief, don't beat yourself up for mental illness aspects that you didn't really understand or fully control during those times... there is a good reason why its called a mental breakdown. If you could control it, you wouldn't do it. Think about that, because it's the truth.
One thing I learnt about all that I've been through, is that sitting around beating yourself up, really achieves sweet f*ckall. Shit happens, you get yourself through it, pick yourself up, dust yourself off, then get on with what you need to do next to get your life back on some sort of track that is acceptable to you, and within your scope of achievement.
Whilst you may not be able to see your kids now, there is nothing stopping you healing trauma, learning to manage your PTSD, recovering as best you can, sitting psychiatric assessment for stability and then being allowed to see your kids again. Mental illness can take away, recovery can giveth back. Courts don't typically punish recovery, especially when expert assessments state you're ok to see your kids. I went through that shit too... and it sucked, but I jumped through the hoops set, passed, and there was nothing my ex could do to then stop me via that method. She used all the PTSD, stability, mental illness BS you can find... she used it, and it worked temporarily, until I sorted myself out and jumped through hoops and beat it.
You can too. It just takes time and hard work.