She's your child. Odds are you'll always be able to see room for maturity. (I've seen that even with my easy child) Like someone else said, she's 20. At some point all of your decisions shouldn't be linked to difficult child.
If she likes older people.... who knows, their company might prove to be a wonderful influence on her.
You have a right to do something that makes you happy. Period.
((hugs))
