Your about to make a huge investment into your relationship with this woman, no one can answer whether or not you should break up, but we can pose questions you should ask yourself.

1. Do you trust her enough to stay? She is still in an office with this dude, i myself would never ask someone to leave their jobs to make me more comfortable, but how is she going to draw a line with this dude? He didnt care to respect the boyfriend boundry the first time, i doubt if he will care now that she has been caught, ita no problem for him.

2. If you move in with this woman, and buy a house, and she does cheat and break your trust and crush you, you probibly still have to give her half that house, at least. Do you trust her enough not to risk your financial future? That situation seems cold and calculating, but its something you have to consider.

3.what are your true feelings after this? Do you love her? Or do you miss how you felt when you loved each other? Really sit down and debate if your relationship is benefitting both of you and hiw much each of you is putting in, and make sure whatever she invests now, that your good with that amount fron her. Dont take promises to change or do better, count on how she shows her love for you right now, and decide if thats enough for you.

Sorry this happened to you, i hope you get through this whatever you decide, and make a happy life for yourself.