Ahhh .... so your little girl has finally grown up and is going to be a Bride. Its a difficult time, you want the best for her and make sure shes happy, but you still remember her saying her first word, picking her up when she'd fall over and scrape her knee, and cuddling her whilst she fell asleep after a bad dream.
Shes met a person that shes convinced that she wants to spend her life with. You might or might not like them ... its her choice really, but still you want her to always be happy and so you're involved in the Wedding.