<human>: Provide a brief overview of the text.

Where do I start...

OK so back when I was 15/16 I has sexual relations with my parents employee [29/30]. Parent was their boss. Mans wife was deployed in Afghanistan. We would sneak around my parent often and it was probably the best sex I ever had. He would frequently ask me "are you sure you're OK with this?" And I, of course, said yes every time. I wanted it and he loved it. Well that ended eventually when he moved away.

Now fast forward 5 years and I'm visiting parent in <insert state here>. Man knows I'm in town and has my phone number (because he still works for parent and databases have closest kin phone numbers). Man says we'll have to hang out while I'm out here. Man has baby now and wife is no longer in Afghanistan. I have AMAZING bf whom I believe I will marry. He is my best friend and I love him with all my heart. 

I try to avoid man but every time he texts me I have these battling thoughts in my mind. It's like there are 2 sides of my conscious. One side says "oh, well the man is an old thing so it won't matter what happens here. It's like an old for-posterity's-sake thing and it doesn't even count if you bang him. It's just meaningless, feelingless sex." But the other (more moral) side that I always listen to is saying my life mantra over and over again: "once a cheater, always a cheater. I've been cheated on and would never ever put my SO through anything like that." 

Now I know the obvious thing to do here is to avoid him but I guess I am asking for more advice on how to combat these "feelings" for older man. I need help on how to avoid the temptation of him and our old ways.
<bot>: back in town with old (older in age as well) sex partner, don't want to cheat on bf. Help!