My boyfriend’s brothers ignore me?

I’ve been dating my boyfriend for 4 months. He has 3 brothers. One of them is very kind and talks with me, while the other ones don’t even look at me.

For example: I was at his place yesterday. 1 of them came downstairs to get something. He walked straight passed me without saying a word / acting like I’m not there. He came downstairs again a few hours later and asked my boyfriend if he wanted an ice cream, since he was about to buy some. My boyfriend said no. The brother didn’t ask me anything and just left.

It’s been like this from the start. It really hurts me, since I feel like they don’t want me in the family or just dislike me. I tried to talk about it with my boyfriend, but he says that that’s just the way they are... I don’t think this is normal though...

Opinions? I’m 22 y/o. My boyfriend’s brothers are in their early twenty’s.
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+1 y
The brothers and I didn’t know each other. They have no reason to dislike me, since they don’t know me at all. They didn’t even bother to say ‘hi’ the first time they saw me.
My boyfriend’s brothers ignore me?
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