@> Lord St. Croix > Thanks for bring that point up, I forgot to add that in my original post. The answer is Yes it is showing in her "wants" panel to marry Jonathan, but also in the "fear" panel it is showing her fear to marry him.
Being that she is a romance Sims that fear is normal with that aspiration. Now Aileen in her "wants" panel she want to marry Jonathan, her fear is getting rejected by him.

I think Jonathan Martin being the Mayor is always dealing with the problems in Pleasantview like homeless people or what roads need to be improved, crime and new building for the city.
That being with fun loving and warm Sofia is a break for him to enjoy life. Now Aileen being a Top Lawyer and a fortune Sims is so caught up in her clients and she is always thinking about the next big buck / money.
( I do notice her personality at time can be cold. )

Aileen Is even thinking about running for "Judge" I notice she not much with the home motherly type ( but I do know Fortune Sims can be good with home and children. )
But to be fair to Sofia I have found that romance Sims can also be good with home and children. ( I know that can be their fear children and being tie down to one person, but I have found they can also be good parents. ) as long as they have their "side dishes" on the down low.

Sounds to me like he should marry Aileen, and while she gets too caught up in her career (she sounds like a very hard worker than would become sometimes consumed with her job), he'll be playing on the side with Sofia.

And whether that leads to him getting caught, well...that's up to you, and to the sims.