Health, I am very saddened by your situation. That is why professionals need to get involved to weed out the unsolicited advisors with the wrong advice! Women are very vulnerable beings especially when they feel unloved. If they do not feel beautiful and they do not love themselves they may fall into the trap of not feeling worthy of being love. This might not be on a conscious but on a sub-conscious level and therefor might feel unloved and vulnerable to an outsider’s influence such as in your case.
I am not about to guess what happened nor am i trying to pry into your situation. I am simply saying that people should not mix in other than to advise others to seek professional help and do whatever is necessary to make their marriage work especially if there are children involved. In today’s disposable society too many couples give up too soon thinking that there is someone else out there that will be a better mate. Unfortunately once they get what they think they want they are very sorry that they made a rash decision and would take it back if they could.
For those meddlers who carry the achrius of broken marriages on their backs, Hashem has no intention of allowing you to unload it nuch 120. You will have to face him with your din v’cheshbon and all the achrius it carries and face the onesh you deserve.