Agree with above, kids come first and survival mode happens for a reason. Could you realistically manage on your own? Obviously if he moves out you may be entitled to benefits to cover rent etc but is there scope for you to take over the tenancy or not? This will depend on many factors such as personal income, if landlord/h-association would allow etc..
@IbisDancer I think you bring some balance to this debate. Some couples have open relationships, are fine with different types of flirting etc. but I do think the response of the husband to her saying she’s erm masturbating was bad. He invites her to include him in her activity albeit perhaps over text only. But there is such thing as a slippery slope..
Now, my DP has a very close F* friend who he will complement, banter with, text now and then. But if he did what you describe, that would not be ok. Saying that, I’d want to speak with the woman, more importantly speak with him face to face like adults, and see if there was a way forward or not. And if so it would need to be crystal clear what was and was not acceptable in the relationship RE close friends such as this rather interested woman 😬
OP your are the mother of his children, from the tone of his texts to you he seems to care about you; there might be a way to salvage this and come out stronger as a couple while keeping the family together as a united unit. This woman is a desperate chancer who can be discarded if your DH is prepared to get onboard with that. Why is she sat at home texting someone else’s hubby in a sexual manner? If she was that great she’d have her own man to please her.
Hope you are ok OP, you’re stronger than you know x
*Female!