Hi Alec, I have read both your threads, last night and this morning.
You have been through so much and handled the whole thing with dignity and as much calm as possible. Your children are very lucky to have you.
Your ex is a shameful shitbag. Did he really have to share the same roof with his children every single night to be prompted to provide for them? Just jacking in his job and leaving it all to you, what a bastard.
I hope you had a nice evening with your friend, that it's cheered you up. I have spent many, many nights worrying about money, it's what I was doing last night! He will search for better paid and consistent wrk once OW can't be taken out for nice dinners and trips to bars, because it sounds like she's into that, after having read a year of your posts! It is totally right, what you said, of being honest with the children about why money is tight, not to alienate them from their father but so they know that you still are someone doing your best, you haven't made any poor decisions to put you all in this situation, they need to know they have a stable and responsible parent no matter what. Which is what you are in spades!
Regarding the kids visitng their Dad and being so upset at how uselss he is, you may just have to hang in their until they are old enough to decide they don't want to go. It's a shit situation, none of you asked for this. Hopefully they will be brutally honest with their feelings and the penny will drop with him. It is terrible that so much is out of your control.
You do have control though with a lot of things. Your kids clearly see you as their loving safe place, they know they have you because you are a brilliant mum. And you have such great friends and family around you because you are a lovely person. If you think to where you were over a year ago, you are in a better place than right after he dropped the bombshell. Ups and downs will come but overall it will keep heading in the right direction. You're doing great.
Hope I didn't repeat myself too much. Hopefully you are feeling less stressed this morning 