So sorry for what you're going through. A couple of thoughts.
You have things to work on. If it was nothing but a MLC and being a lesbian, there wouldn't have ALSO been a list of things you did wrong plus the statement that all her men (suggesting YOU included) have disappointed her. Work on your things, become a better person, better dad, and someday for someone a better partner. Gives you something to keep your mind on and helps with the hurt.
Your W may be a lesbian and that's that, or she may not. It's beyond your control. If you love her, work on the things you can fix about you and give her space for the journey she needs to take. If it gives you hope, I can tell you my sister became a lesbian after about 15 years of marriage with teenage and elementary schoolage daughters. Blew up the marriage, which was blowing up anyway because of many other dysfunctional relationship issues. Told everyone including my homophobic parents. Lived as a lesbian despite the challenges that caused her daughters. Fell in love, planned to get married to a woman, the whole nine yards. A few years later, became not-a-lesbian, expressed lots of regrets about her ex-H, ended up marrying a man. If her ex hadn't been remarried with a new kid, the story might have gone differently. You just never know. All you know is what she's doing now. See if you can take each day as it comes and not predict the future. See point 1 again, you have stuff you can work on.
Three - there is no point of no return unless one of you is dead. I had so many ideas when I first started here. Separating the bank account seemed like a point of no return, but it didn't turn out to be. Telling our parents seemed like a point of no return, but it didn't turn out to be. Telling our kids REALLY seemed like a point of no return, but in time and with a lot of effort, even that could have been overcome. Looking at things as points of no return is predicting the future, a futile exercise, and self-limiting. All around there are examples of people who divorced and remarried the same person, and people who almost got divorced and then didn't, and people who were gay, and then weren't.
Your only concern is to learn and grow from this situation, and be the best you as each new twist and turn occurs.
Good luck.
Adinva 51, S20, S18 M24 total 6/15/11-12/1/12 From IDLY to H moving out 9/15/15-3/7/17 From negotiating SA to final D at age 50 5/8/17-now: New relationship with an old friend __ Happiness is a warm puppy.