Stretch Marks

Im very active since im doing volleyball right now and my body is always changing. i was changing to take a shower and noticed new stretch marks. i have some on the back of my thighs and butt but now i have someone in the inside of my thigh. im just now noticing them and i wish i didnt. i know i should embrace them but im not very good at doing that like i was when i was younger. my boyfriend just calls me his little tiger and that makes me smile but i still dont find myself as attractive with stretch marks. i havent worn skirts or shorts or dresses that show my thighs because i dont want people to see them. i dont know what to do and i know i cant prevent strech marks. i just want to feel pretty with them again.