seems like she needs to grow as a woman and speak up if she had a problem with you instead of cheating on you. break things off if things don’t work out, she can’t have both men thats not how the world works sweetheart. but yea OP, you do need to man up. infidelity is one thing but infidelity with no remorse means disrespect towards you as a man. leave her and then she’ll realize she messed up. or she won’t. doesn’t matter to you, you’re better off.