I've found that since I'm rather small inside (never had a hymen though), I need to be gentle for the first minute or so of sex. Basically, I go on top of my boy, lead him inside, and just sit there, holding him inside while my body relaxes and stretches a bit. Otherwise, it really hurts if I try to go at it right away. After the "getting used to" part, I'm perfectly fine and it's really enjoyable. Maybe try something like that? Some gentleness?

good luck!