Your a guy it's normal, ! Do you see your ex on a daily basis or do you literally think of her out the blue ?
Yes you should.
Everyone thinks about a past love every now and then.
but a little spanking is never a bad thing...
THAT could be a little bit of an issue... but it could be because you are sexually bored with your partner. You should try experimenting in the bedroom, spice things up a little so the thoughts of the other woman dont pop up!
Sounds like it!