Hi, welcome to the forums! Thank you for reaching out, it takes a lot of strength.
Honey, I can relate so much. Not about the husband and kids, but about a past attempt and being afraid of repeating.
The good thing is, to fix a problem you have to realise you have one, and you do realise that which is fantastic (kind of? not good that you have a problem obviously, but good that you realise these thoughts are unhealthy).
My recommendation to you would be to go and start seeing a therapist or find someone to talk to about all this. Do you already have one? Any good friends or other family you can confide in?
I think the best action of call is making a list of things you are thankful for. Your beautiful kids need you in their life. I grew up around a special needs older brother and ended up becoming a second mum when my parents would leave for long periods, I promise that they love you and care so much for you, even if sometimes it may seem like they don't.
In regards to work and relationship wise, I am not qualified enough to comment on that (again, I think a therapist is your best point of call) but I do not that when we feel stressed or overwhelmed, small things can seem like very big things and it all piles on top and suddenly you are drowning.
Just take it one step at a time. You don't have to fix everything in one big swoop, just baby steps.
You have so many people that love you, and you are not alone in feeling this way at all, you should be proud of your immense strength that it takes to survive and go on day by day when you are feeling overwhelmed.
You are strong and powerful, and I am so proud of you. I am rooting for you, it will all be okay. You have value in this world, and you are so important. Don't ever forget that, OK?