Jealousy?

Nyosha • 19 year old student in downtown Toronto! Currently in love with my awesome boyfriend. ☺️💘
Hi ladies! I'm wondering if anyone has been in my position before...
My boyfriend and I have been together for 6 months. Everything has been going great! 
While he is my first boyfriend and sexual partner, I'm one of many women that he has been with. He's only a year older than me but in he has many wild stories involving sex, partying, drugs and alcohol
I know he only loves me, now. And that he's changed his ways. But the thought of him with all those other girls drives me absolutely crazy! How can I stop being jealous and just move forward? 
Any advice? Thanks so much!