I am not sure the reason this should come up in the discussion with your significant other. It is certainly not something I would bring up...I would treat it as I would past one-night stands and that is that it didn't mean that much emotionally and there is no reason to discuss it. In the relationships I have had and may have in the future, I don't want to know or particularly care about her sexual past and will honestly wonder why she wants to know mine. I am unlikely to see a provider in a store or restaurant, and we are unlikely to greet each other if we did. So not likely to have the "Hi" and SO ask, "Who is that?"
I also do not feel particularly guilty. I am not very active in the realm anymore, but I don't feel guilty about my past activity. I just don't find it to be immoral. There is a difference between immoral and illegal. And while some of falls within vice laws, I do not think it is immoral (except in rare circumstances in which providers are forced to provide service -- the idea of which I find disgusting). As long as providers are there by choice, no one is being exploited. Most of them are making a better living than me. Morally, I do not consider this much different than a one-night stand or a booty call. At least in the hobby, no one is lying simply to get laid.