My boyfriend is 20, I'm 33. We started dating on his 19th birthday (LOL). I broke up with a 40 yr old man to be with him. Sounds weird. but for 20, he is much wiser than most 40 yr olds, but still a kid at heart. Life experiences or difference in life circumstances seems to be the biggest obstacle. I have been married, divorced and I have one child whereas, this is his first real relationship. so for that reason, things can and will be difficult. i remember how i was about relationships when i was 20 so i tend to be understanding. But we are on different tracks in life which is hard. And someone that young is not always sure how to deal with a girlfriend who has to put her child first. Most 20 yr olds dont have to think about those things so mostly i feel its unfair to him. But on the flip side, its not always fair that my man does not have a solid career and he doesnt live on his own but he is only 20.