<human>: There is this girl that me and my SO knows. I can't say I am friends with her because every time I try to talk to her, she downright ignores me. Like, literally. Every, single, time. But when someone else talks to her, e.g., my boyfriend, she is very friendly and would reply spontaneously. I honestly cannot figure out why she would only do this to me, we've not had any arguments or whatever.

If I were my boyfriend I would've toned down my interaction with this girl just because how she has been treating my SO unfairly. This is the way I think- If someone is unkind to my SO, I can't be kind to that person too. But the way my SO thinks is that, if someone is unkind to me, that's between that person and me, and he has nothing to do with it so he can continue to be friendly with that person (so long as that person is friendly with him). 

Am I right to be hurt by this or am I just being childish?

Summarize the given text in a few sentences.
<bot>: BF is kind to the person that is unkind to me - am I childish that I feel hurt by this? Need second opinion