When Your Girlfriend Tells You After 10 Years..Theres Nothing Better Than The Real Thing

me and my now ex girlfriend of 10 years recently got back together again and our sex life just isnt. Shes gained a lot of weight and im just not sexually attracted to that...but we had sex anyway. she looks at me after were done and says...it doesnt feel as good as a real ****. Ill teach you she says. Now the entire time we were going out she claimed to not be turned on by guys, that they couldnt satisify her sexually....for years i believed this. now shes shocked that i wont take her back because i know shell just go behind my back again and **** another guy...just like she used to and deny it. The problem is...i cant get the images out of my head...detailed images of things shes done with more than one guy at a time. Things she told me shes done with A LOT of guys..sometimes 4 at once. She was high and dont remember telling me all of this. Now she says she said it to turn me on...that she didnt mean it. Please confirm that i should run as far away from her as possible and never turn back. I would have to be nuts...wouldnt i?