I'm upset with my mother, is it fair?

I'm upset because she's busy out on a 2 week trip with her 3 female friends. She saved money for that, for herself. It's not even a trip to a different city or state but towards Brazil and Chile. By the time she comes back, she's going to be broke. It's not the first time she has saved money for herself. Last time it was for a nose job, which she never needed. She's been acting like a teenager. No, she's not single. My parents are married but she's acting like she were single. All of the sudden she wants to go on trips with her friends, go to friends reunions and parties, etc.

Meanwhile, my father and I are spending money on my upcoming wedding. My mother won't collaborate on anything (she'll be broke again once she comes back from her trip) other than just presenting herself.

I feel as if she doesn't care about my own day. She chose her trip, her own self over me; her only child.

Updates
1 y
My father and others in the family are all involved the wedding expenses and preparation meanwhile my mother is on another country with her friends, getting drunk, going swimming and acting like a single girl, wasting money on worthless things.
I'm upset with my mother, is it fair?
Post Opinion