It's pretty normal. I don't think two humans are really meant to mate for life and have no other sexual partners, in fact, the copius amounts of "cheating" going on pretty much proves that imo.

Personally, that's why I'm poly, and I think that actually leads to longer, more healthy relationships, because there are no unfulfilled desires, no secrets, no need to hide anything. I can't think of any reason why I would ever break up with the person I live together right now.

I understand that that's not possible or desired by everyone, and it's not even my suggestion, I'm just mentioning it because it's relevant to my true advice:

There is absolutely no reason to talk to strangers first about this. The fact that you're coming here first instead of talking about this with your spouse indicates a lack of comfort talking about problems/desires. I for example would have almost immediately told my partner about that other opposite sex coworker I like to talk with, I suspect that you haven't. It seems to be such a big taboo to talk about interest in other people in traditional monogamous relationships. But most of the time, when I talk about interest in someone else with the partner I live with, or they with me, we actually become closer again and this interest in another person decreases, i.e. our bond gets stronger.

So my actual advice is: go talk about literally everything with your spouse. Open your heart up completely. It either leads to you two becoming closer or drifting farther apart, both of which are very desirable outcomes, since if you are completely open and drift farther apart, it means this person is not actually right for you! You might get the opportunity to look for someone that you're more compatible with! That is an amazing opportunity in my opinion, because everyone deserves to have a partner they're completely compatible with.