Having fully investigated both flat and drop bars, I can say with certainty that I don't know what is right for you.

I do know that having a nice flat-bar bike certainly wouldn't hurt any, and the wife would surely accept it since you can't ride the other one without excruciating pain (you did mention excruciating pain, I thought? )

Aero losses will be minimal unless you were used to riding int he drops. I found I could drop my elbows below the bars and get pretty low with a flat-bar. Not as comfortable, but unless you are hitting headwinds or racing ... who much cares about aero anyway?

I often think of buying one (like about every time anybody here considers it.) the only reason I don't is because I cannot ride all my bikes enough already. So ... treat yourself----for medicinal purposes Only.