<human>: Can you provide a brief rundown of the text in within 3 sentences?

He has never been anything than wonderful to me. He accepts me in all my social anxiety craziness. But if I'm honest, I stopped being attracted to him a while ago.

Partly because he's started to grow a beer belly, but also since I started having dreams about other guys. 

One guy in particular with whom I used to work. All I can think about is sleeping with this guy. This has been going on a little over a year.

The sex isn't *bad* with him when I can get in the mood for it. But I don't crave it anymore.

I'm afraid of what I'm missing out on since my current boyfriend is my first and only.
<bot>: What do you think? Is sleeping with multiple people that important? Is that something worth worrying about? Or am I just experiencing normal 5 year relationship doubts?