I think my boyfriend isn’t proud of the fact that I’m his girlfriend, why?

I had found out my boyfriend was cheating with another woman. He had told her that I was just an ex. I texted her and told her otherwise, that I was really his girlfriend. After that, I thought they had stopped communicating. They didn’t. Only then did I find out after I told her I was actually his girlfriend and not an “ex” in some messages I read after I cleared that up he did mention me as his girlfriend but not in a good way. The texts said things like “My girlfriend gets off at such and such time. You can come over then.” Or “We can go out on this specific date. My girlfriend won’t be around.” And we actually live together. So it’s like he was no longer calling me an ex but it still was very disrespectful.

I think my boyfriend isn’t proud of the fact that I’m his girlfriend, why?
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