Been there op but not a best friend but I thought a good one
I know you don't want to deal with stuff but I'm afraid there are certain things you really MUST Deal with asap
1 close the joint account! My ex within DAYS of everything coming out emptied the joint accounts and left me up shit creek! Do not risk being in that predicament (and I didn't think he'd ever do that and neither did his own family! Do NOT assume he will play fair at all!)
Open your own sole account WITH A DIFFERENT BANKING GROUP there's a loophole I think is still in place where if you have a joint account with someone if they run up an overdraft funds can be removed from EITHER party's other accounts to cover the debt
2 secure any other valuables inc official documentation for you and dc - my ex also one eve when he knew I'd be out went back to marital home and took valuables inc family heirlooms of mine and the computer
3 cancel the wedding vendors asap - the longer you leave this the more likely you are to lose deposits etc (I used to work in this industry - after my own divorce weirdly)
4 get a claim with cms started NOW because they only backdate to date of CLAIM not when you split and the sooner you start this the better. That said don't depend on cm it's poorly enforced in this country
5 get legal/financial advice asap
6 sorry about this one genuinely - but get a full Sti screening asap. I was LUCKY and despite him not practicing safer sex there were no issues but I know of others in real life and on here who weren't so lucky and early dx and treatment is important
6 as much as possible keep all communication in writing or at least confirmed in writing for evidence of what was said
Regarding taking care of yourself:
Sleep wherever and whenever you can, I couldn't face sleeping in the marital bed for the 1st few months, and slept on the sofa. I didn't really admit it to myself at first and left myself uncomfortable and cold sleeping just on a cushion with a throw initially. Then I thought "this is daft" acknowledged I wasn't up to sleeping in the bed yet and sorted a proper pillow and a quilt and was much more comfy and slept better.
When I'm stressed I don't eat I can't cope with it. Gp at the time made what seemed an odd suggestion but actually made sense - slim fast/nutrisip type drinks. They not only have enough cals but they're also fortified with all the vitamins etc you need. She also prescribed iron supplements for me. So I basically lived on those, sometimes soup with the occasional slice of toast for a while - better than nothing
Don't beat yourself up or set time limits on yourself - it'll take as long as it takes for you to start to feel like yourself again.
What he's saying and you've discovered and it sounds like what she's said to her husband etc is very much "cheaters script"!
I wish I'd known about mn back then my exes behaviour would have been identified much earlier on!
Mentionitis
Possessive with phone
Suddenly "working late" when previously he'd been a clock watcher
Rewriting history
Blaming me for our relationship not being like honeymoon period!
Claiming he'd not been happy for years (bullshit!)
Denying the affair (despite a baby being conceived!)
It really is quite something! And astonishing how many of them follow the script even though I don't think they discuss with other men/cheaters
You WILL get through this - you'll have days/times when you don't think you will but you will
I understand what you're saying about not wanting the children around her, unfortunately you don't get a say in this so as soon as possible you need to get your head around that - it's hard!
In my case she had babysat dd and knew her well so it was easier from that pov but emotionally for me it was rough!
DO NOT trust the in laws, mine were generally lovely but ultimately he is their blood not you
Don't tell them ANYTHING you wouldn't want him knowing immediately
He will promise all sorts at this stage yep - it doesn't last long! DAYS in my case op DAYS!
Don't believe the marketing - my ex and his ow are now married with 6 kids of their own. However they tried to convince me all was rosy, then over the years I have learned from mutual friends and even ex in laws have let things slip that they are in fact miserable together! She won't leave cos she's afraid he'll screw her and her kids over the same as he did me and dd, he's a serial cheat who won't leave either
I felt awful when I was believing he was being a better husband and father with her than he had been with me. My mum kept telling me people don't change and not that much that fast and not permanently - she was so right! She obviously has more life experience than me and although she hasn't been divorced herself many of her friends and family have and she's supported them through similar situations and was reminding me of some of them which I knew of. I still struggled to believe it.
Then a few things worked their way back to my ears, the whole situation really culminated in the DAY before THEIR wedding - he propositioned me! Honestly! I mean Wtf!! That was the point at which I knew all was not as they were trying to portray it! Even so I learned even more after that inc former sister in law letting slip things like he questioned the paternity of their eldest, that he almost left her for HER oldest friend at one point...
But that's really down the road
For now - get the money and legalities sorted asap! You WILL kick yourself later if you don't
Oh yea - also if you are now eligible for benefits now he's left you need to claim them asap too, same as cm goes from date of claim.