You are completely and utterly wrong. Many Escorts avoid relationships while they are working because they are Monogamous and it would be going against the grain to work and be in love with one person.
Many Sex Workers choose the occupation, because it is the route to a better life, not because they are sex mad and rampant.
Many Sex Workers hold back with clients, so they can keep something special between themselves and he person that they love.
Most sex workers view it purely as a 'job' and not as their sex life, so if they were to change jobs, it would not be a burning ambition to still have sex with many different people, it would purely be the start of a new chapter in their life and if they wanted sex, then they would go to their partner.
If anything it is the Sex Worker who would be suspicious of the Client they were settling with, as they are often the ones that desire variety or were seeking sex within a relationship.
Personally I believe in treating every person as an individual and finding out the reasons why they are where they are in life and what their motivation is. I feel it is wrong to put people in boxes and make huge assumptions on their feelings and their needs in life. We all need to be loved and we all deserve love, it's what we do with it that matters.
I would say the question here for me is more to do with if the sex work continues once you are a couple and if you can handle that, or do you work towards leaving the profession and moving on to another chapter of life together? When you love someone you are willing to compromise and look for solutions. If not, it's not really love at all and that is for both sides, not just the sex worker.