My gf who is a Christian thinks that I should ask my mom to end some restrictions because i'm too old for them?

Sounds like there are two extremes here: One is your g/f seems to have too much freedom and is pushing that you have the same to accommodate her. She does have a point though about the rules. You are not a kid, you are over 18 BUT if you choose to go to sleep at a certain hours, hey more power to ya. The tucking in and pj's is weird but cute.As long as moms isn't giving you any sponge baths. lol Te 9pm curfew is good training but not for a grown man. You decide whats best for you but remember, you live under HER roof and will respect and abide by her house rules. Now why your sis doesn't have the same rules is beyond me.