Is it right to???.......?

Is it right to go out with ur ex-best friends, ex-boyfriend becuase i am and it feels kinda wierd even though i have always wanted to go out with him, because he makes he feel good and he knows who i am, u kno that song from kelly clarkson you found me well that is the phrase on what happend with me and him so yah, even though my family hates litteratly hates my ex-best friends family, and even though i made a promise to my ex-best friend that i wouldnt go out with him i wouldnt flirt with him or anything like that, and even though she knew my ex-boy friend was cheatin on me and she didnt tell me is it still right to go out with him, even when i feel like i really love him,.......???