Looking for some direction!

[help123]

First time poster looking for some direction.
6 weeks ago my wife and I decided to go to counseling individually.
She told me she was tired of my negative attitude and how I was dealing with the kids. "When I got mad at them she saw the light diming in their eyes".
After much self examination, I did realize that I was directing a lot of my frustrations towards them when in reality it was my wife who I was mad at.
She is an endurance athlete and I believe she is addicted to it. Over the past 7-8 years with all her training I was forced to be the main caregiver to our children and the frustrations started to grow.
Since my kids were the ones around all the time I did direct my feeling toward them.
Just poor attitude, and unpleasant to them at times.
I realized this pretty much immediately and made some drastic changes.
I was really unaware I was doing it.
At the same time, she went to counseling for "she has pushed herself so far away from me that she doesn't think she can every find her way back".
Two weeks later, I find out she has been in an affair emotional at first, then physical for about 2 years.
I am devastated by this revelation but it is not in my nature to quit on our marriage and want to do anything/everything to fix it.
She just wants out because I think this other guys just makes her feel good.
She has told me she wants a divorce and that she loves this other guy (just got second divorce and has had multiple affairs including my wife) She cant see any of that.
I know that this affair is a cause of our underlying problem that I was so negative and didn't support her in her athletic adventures, according to her.(we rarely communicated about this) It used to be things would get better after the next race for us, but then turned into after the next race, there was just another race. I have always loved her and did support her, not that she sees, but thought I would just let her do what she loved and eventually she would come back to me and be appreciative of what I had done.
She cant see all the support that I did give her! All she sees is that I wasn't in a great mood all the time and now all she can see in me is negativity which is really far from the truth!
She holds onto 3 times in my life where I got really angry and was probably scary to be around brief instances of maybe 5 minutes each. No violence but just really angry. She is looking at apartments to move out into a nest situation where we will both stay there when its not our days to have the kids.
They will stay at our home and we will try to make it easier for them.
This will be short term until divorce and then we will have a more permanent living situation.
I don't want this.
I would love to break my wife's determination to get out of this marriage but don't know how! I really do want to make our relationship.

I know it will be a tough road to travel but I am ready to give it a shot! Help Please!