<human>: Give me the gist of the text in a nutshell

I've been with him for coming up to two years and until the last month or so, we've had a great relationship but I've noticed more things happening which are adding up to making me feel bad about myself. When I'm actually with him, I couldn't be happier and I get on with him better than I do with anyone else but there are issues building up.

It started while we were on holiday and while we were walking up some stairs, a girl in front of us who had a very large ass was wearing a pair of shorts which showed off half of it and he was blatantly staring at it in front of me, then when I semi-jokingly made a comment to him about him staring, he said something like "Yeah but her face wasn't that great". 

After that, I can't remember the conversation before it for the context but he made some comment about how I don't have a big booty.

The last few times I've sent nudes to him on Snapchat, there was no response back. It used to either turn into sexting or the next day, he'd text me something like "Thanks for the photo ;)" but now I get nothing back from him.

The most recent one was the other day when he initiated sex but I was on my period so rather than me giving him a blow job or whatever, he stopped immediately, got his phone out to look at porn and wanted instead while basically completely ignoring me until he was done. 

I've always been very insecure about how I look even though I can see that my face and body shape are considered conventionally attractive. He's also very conventionally attractive and his relationship with me is his first one. None of these would bother me anything like as much if it wasn't all of these happening so soon after each other.
<bot>: Feeling insecure because of a lot of smaller things my boyfriend is doing- looking at other girls, ignoring sexts and masturbating instead of sex.