<human>: My boyfriend(26) and I(32) started dating five months ago and made our relationship official just a few days ago. During the dating period we set our boundaries as mutually exclusive. We hung out a few times a week and talked on the phone nearly everyday. He works 7 days a week and doesn't have time for much else. Yesterday I went to go put a risqué pic as the background on his phone while he was downstairs. For the first time ever I decided to look at his messages (he's always looked at mine). Up until three weeks ago he had been talking to various girls. Asking them on dates, one text said he'd be right over after a girl told him to come over while she was in the shower. 

I confronted him and he admitted to talking to girls and flirting but swears he didn't do anything more and it was more of a validation to him to make them want him. Until this point in our relationship he has been the sweetest man I ever met. He brings me flowers, opens doors, communicates well... All of the good stuff. He said that he stopped talking to them when he decided he wanted me to be his girlfriend.

Now I'm torn. We weren't official at the time so I'm not sure how mad I should be. I am hurt though. I've completely fallen for him and I think we have an amazing relationship. Am I letting my emotions forgive him too easily? Am I playing with fire and setting myself up for disappointment? Advice please.

Summarize the given text in a few sentences.
<bot>: dated a guy for 5 months, now we're official. Recently found out he was talking to multiple girls the whole time we dated. Says he stopped now. Should I believe it and forgive And move on?