Relationship advice?

So my boyfriend of two years liked this girls picture. Wasn’t a big deal as I normally don’t care who he is friends with or who’s posts he likes. However, this picture was my friend (he didn’t know she was close to me) in a revealing bikini, in multiple poses. I still wasn’t too worried, until he followed her and voted on the meter that she was “hot”. I confronted him about it and he lied the first time saying he didn’t like the picture. After I got mad, he explained that the voting was an accident, but that he was sorry for liking the picture and how much he regrets it-blah blah blah. This normally isn’t like him at all, he’s quite loyal. I explained I’m upset and he says he deserves it, but he doesn’t want to lose me and is willing to rebuild my trust. And if i’m being honest, I don’t want to lose him either. It just made me mad that he lied about doing it. Do you think it was a legitimate mistake? Should I forgive him and try to make things better? Am I making this a bigger deal than it needs to be?