I inadvertently read a text on DHs phone last night. I've never been through his phone before but it seems that for years he has been texting another woman on and off. I read the whole discussion (dh was out running). One will initiate a conversation and they'll exchange a very long message or two and then it'll pick up again a few months later. He regularly compliments her appearance, always adds numerous kisses and most recently, in response to her saying she's seeing someone, he's admitted he always had some feelings for her. The reply he received today was her saying she had thought about it before too and he should have said something before he got married. I'm heartbroken. It seems she is currently working abroad and prior to that lived at the other end of the country. I have no idea how they met but they knew each other before we got together. I'm 100% sure they haven't actually seen each other in years.
What do I do? Part of me wants to confront him but I don't want him to know I've looked at his phone. I don't doubt that he wants to be with me - we've made so many plans for the future and we've recently started TTC. He's been fully committed to all of this but now I feel second best. Am I overreacting?