Well, I went back and read your info and this is what I think. I think for you, an older (at least 6-7 at the minimum) horse would be best for you. (a belgian would be GREAT! I love them!)
There is a saying. Green+green = black/blue.
Now, I wouldn't call you exactly green. You DO have experience. But, it has been a while so it is almost like starting over.
I would suggest lessons. You could take some lessons to "brush up" on your riding skills and "see" what exactly you would like and what you can handle. Personally, when I ride (and I'm older too) I don't really like to "fight" with a horse. I like push button horses that do what I ask them to do. My philosophy is that I don't mind a horse that "goes" just as long as I know that they will "stop"! My husband, who doesn't have as much riding experience as me, prefers an even MORE push button horse than me. (He is currently riding an ex-Mounted Patrol horse) She is not a "plow horse" per se, but extremely well trained.
Some people, (like my 25 y/o daughter) like a "challenge" when riding. (sounds a bit like "your love") It does not sound to me like the two of you can/should share a horse. It sounds like you want two different things in a horse. But you said that you eventually want to anyway that should work out.
I would suggest getting a calmer horse first (yours) and then get a more "spirited" horse for her when the both of you are more confident. (unless you can afford both now.)
I would skip the "green" horse at this time. Green horses are a dime a dozen and very easy to find. I would continue looking for a more experienced horse. They are out there. They cost a bit more, but they are worth it. Believe me, you will pay either way, either in a well trained horse or the hospital bills for an untrained horse.
Good luck and let us know what you get!