Most Helpful Guy
In formal circles the word girlfriend translates into unpaid prostitute. In many countries it is a violation of Moral Turpitude and with The USA the word can remove a woman;s visa status. The USA will only issue a fiancee visa for women if they say the word boyfriend.
The word girlfriend carries a nasty meaning for people who know.
Most Helpful Girl
He doesn't want to take your relationship seriously because he was wounded in the past and now he's scared.