Opinions on liking pictures on social media?

Hi everyone I’m in a serious relationship and it’s only been 7 going to 8 months because we want to get married one day😊 but I’ve been feeling very insecure lately because I’ve noticed and it was a pattern before and after we started dating how my boyfriend would like pictures of girls showing cleavage, their butts basically half naked. At first I ignored it but then it became something big and it hurt me deeply. I confronted him about this with another dating couple and I expressed to him how it made me feel and we were able to work things out. But then I noticed it again and I told him off he gave attention to this girl and he excused it but I told him that it wasn’t okay, and this really affected my self esteem and my trust in him. There is more but this happened a couple days ago I noticed that he liked another picture and it was a girl showing her butt and I was done and I basically told him that he needs to figure himself out because he keeps giving these girls attention and I basically said how hard is it for you to scroll down and not give it importance then he started excusing it with it’s how men are “biology” I can’t help it. Then I told him that you just lack self control and he’s excusing himself and I can’t be putting all the work on my part, I literally don’t put myself in situations that make me struggle and he always looks at girls on the internet and in person. And I told him I don’t want to marry an immature guy who can’t help me feel secure. But what do y’all think about it ?

-it’s affected my body image so much I haven’t been eating well

When should the limit be?

Am I not being a Christian?

And then he told me that he is allowed to think other people are attractive and I called him out I was like that is such a disgusting entitlement that gives you no right to act on that?

I am crushed broken and I don’t think I’m good enough