@snowmanak907,
I would not find it strange -- but then I am putting myself in the position of spending time with one of my uncles. Not knowing the dynamics of her family that is all I can do.
My uncles whether blood uncles or not, were/are all looked at as similar to like a dad figure. Especially any that I would be particularly close to. It would be like hanging out with my dad or even a significantly older brother. Most uncles you know as a young child through being an adult. It would not matter whether a blood uncle or not if I were close to him.
It wouldn't seem weird unless there was some underlying item that you have not made us aware of. She is probably upset or offended if she simply has a close relationship with him and you say it sounds weird...it would sound like you are accusing her of something or else think her relationship with a close relative is weird.
I had an old boyfriend that used to say things to me if he thought something my family did or acted was different - he would tell me isn't that weird. Of course you take offensive you love your family and all family dynamics are different.