<human>: Can you summarize the given text in a few sentences?

On one hand, I would never cheat on my girlfriend.  She is amazing and fulfills me both mentally and physically.   

On the other hand, I can't help feeling like I'm not ready to be with one woman for the rest of my life.  I never saw myself settling down before 30 years old. (Admittedly a self imposed, meaningless benchmark) I'm in a young work environment surrounded by a lot of people my age and there's temptation everywhere.  Not to mention, while I am very happy in my relationship, I do not envision marriage anywhere in the near future.  

This just feels like a grass is always greener, damned if you do, damned if you dont type situation.

Does anyone who's been in this situation have any advice?  Is my dick just getting the best of me?  Is that a bad thing?  

I'd be more than happy to answer some questions to provide clarity on the situation
<bot>: In a happy relationship of a year and a half but working in a young environment and tempted to cheat. Also, not ready to settle down.