You’re right that many agents suggest that. I see nothing wrong with that part of your query except that maybe it’s not necessary to say you’re choosing to submit–kind of obvious. Just something along the lines of “Because you sold XXX by XXXX, I think you may be interested in my novel XXXX which will appeal to similar readers.” 🙂
What is the pivotal event that starts the middle of your novel? It’s usually about 5 chapters in? Is the this when she finds out her soulmate is married? Or is it the “brutal attack” and I would strongly advise being specific about what this attack is. Generic descriptions just dont work in a query.
You really need a “hook” in your query and you don’t have it at the moment. Starting out that it’s set in Chicago or with a generic sounding list of problems doesn’t work. You want to be specific and make it as exciting or interesting as possible. I don’t even know what a “brutal attack” is. I’d skip the enraged with jealousy though which hardly sounds sympathetic in a main character.
Kristin Nelson did a great series of blogs on writing a query in which she advised studying the back of book blurbs on similar books and using that method to writer your query.