leg strength ?

I am MS and I have right sided weakness. I was unable to walk without an aid up till a little over a year ago. My right side is alot weaker than my left. My leg strength is aweful. I find ridding with my stir-ups up high makes me feel more secure like I can put more pressure in the stir up if needed. But my body isnt aligned correctly when I sit this way in the saddle. I have tryed lowering the stir-ups but I seem to lose my balance more . Does anyone have any ideas that might help me ?
Forgot to mention western saddle . And when I say stir ups high I mean to where my knees are bent . Not sure if I am making sence LOL

Forgot to mention western saddle . And when I say stir ups high I mean to where my knees are bent . Not sure if I am making sence LOL