Shoulda just sprung for the Offroad Adventure II package. That gets you Quadra-Lift, which lowers the vehicle like 2" when in park for easier loading and unloading. It also does automatic load-leveling, lowers the Jeep at speed for better aero, and allows the vehicle to be lifted almost 2" over normal for offroad use.
I suggest running boards. They aid in entry/egress and increase resale value, unlike a lowering kit which decreases resale value and damages handling.
That said, I'm 5'4" and have arthritis and a permanently disabled arm, and I have no trouble getting into or out of any stock Grand Cherokee. If your wife is having a lot of trouble, I can only assume she's somehow worse off. In that case, I offer my condolences.
1997 Grand Cherokee Orvis Edition
1998 Grand Cherokee 5.9 Limited
Shoulda had a V8