Obsessed with the past

Hi! Hoping for someone to offer words of advice to free my mind and let me enjoy my relationship! I have been in a relationship with a beautiful, smart woman now for 7 months. When we first started dating, we were not emotionally as connected as we are now, we shared many things about our previous experiences. I have had my fair share of relationships. And my partner has too, some of which now seem to haunt me which is why I write this. We live in a very small town and it is not easy to avoid running into each others past continuously. For example, My partner used to date a local drug dealer for a couple of years and was using quite a bit, as well as helping with the business. Even though that was 10 years ago now, some people in town still refer to her as a coke hoar. This bothers me quite a bit. Another example is a couple years ago she dated a 19 year old who was a former student of mine. ( I am a teacher). She was 10 years older than him. They had a year long relationship based purely on sex, nothing else. I don't run into the kid much but I know his friends. Anyway, we have been talking about marriage lately. There are many more such stories and the closer we get to planning our life together, the more I Sam bothered by these. I think she is amazing, but these silly things that should not matter, linger in my mind and prevent me from getting as close as I would like. Sometimes, I think about ther sex she had with the teenager and it prevents me from getting intimate with her. I know I should just accept the person and move on, but I am having trouble. The thoughts will not leave as much as I want therm too. I want to carry on and be happy with her but this is tormenting me and could destroy the relationship. Any advice??