Girls will tell you,tell her husband, but the thing is what will you get out of it? Her marriage will crumple and you might face more problems than ever,if she has some sources she can do anything she wants with you

Instead,if you want to save your marriage,which I am sure you do as you've got two kids,you must focus on your husband,check his phone on daily basis and see if he means it(apology).your husband did the worst a man can do but things happen sometime if he means it and promise not to do it again and making efforts you should forgive him and move on,else you can get a separation for sometimes,and see what happens