I would have no problem dating an SP, but the relationship would have to remain relatively casual while she is working. I would not (claim to) go exclusive with someone who has sex with others for a living. We all know that SP's sometimes enjoy that sex so I wouldn't limit my options either. That would mean, for me, not living together, but just casually dating.
If she ever quit being an SP I would have no problem taking that further and if it was right I would have no problem with marriage.
An important caveat there is that I would never ask her or force her to quit being an SP, but she would probably know that things couldn't go to the next level while she was one. That is a bit of a tight rope to walk. The issue is you cannot control people so if you pressure or coerce her to quit you may find out she had secretly retained a few regulars or still works the odd shift or something. So it had to be genuinely her choice to quit.
Anyway, my expectation is that the SP would have the bigger emotional issue. Most SP's rationalize what they do as business, something they do to earn money. Clients are the reverse, we spend money for sex. Any SP knows that the odds a client would stop using SP's completely is pretty low. In the back of her mind she knows things other women may be more oblivious to.
Once an SP exits the business SHE may be the one with the trust issues around a former client, and her wariness may be well placed.
People like to say one a prostitute always a prostitute, but it is even more true to say once a client, always a client.