Sorry but I have 0 sympathy for someone who lives a lie for years, even to the point of having children and then leaves for another man/woman. If you’re gay then who cares. But no-one has the right to hurt others as part of that.
No-one wakes up one morning and decides they’re gay, she will absolutely have known while deceiving her husband and marrying him and having children with him under false pretences.
And if this was a man who had left for another woman nobody would be telling the OP to accept it.
Also, given she’s now decided to admit she’s gay my thinking would be that she’s probably been shagging around with other women for the duration of her marriage.
There have been plenty of posters on here whose husbands have come out as gay and who it turns out have been seeing other men for the duration of their marriages.
She doesn’t need to be remorseful over the fact she’s gay, she absolutely should feel remorse for the way in which she’s treated her family.
If my parent left for someone else, be that man or woman, the fuck would I accept it, and would have nothing to do with them possibly ever again. I certainly wouldn’t want anything to do with their new partner. And I say that regardless of their sexuality.