Dating

It's weird I like more my girlfriend's ex than her?

I don't know, he's very cool and we have been becoming best buddies
She's complaining she's feeling excluded but I don't know her ex is much more likable than her and I'm starting to think she was the wrong one in the relationship
Maybe she's the wrong one in our relationship too?
I mean I like her but even when she was together with her ex I liked him more. She says her ex is the third wheel but we make her feel she's having the third wheel and I admit I kinda feel bad about it.
It's weird I like more my girlfriend's ex than her?
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