OP, if you already were aware of possible changes to method, I don't know where you can find a slide assist, sorry.
OTOH, I'll assume you've been taught variations on the sling-shot including punching through with the shooting hand, and cocking the hammer first to get rid of mainspring weight. Then again, assuming only causes problems, so just in case - you can check
http://corneredcat.com for possible help with technique.
My mother has weakening hands... She found the taller slide of a SIG to be easier to manipulate than some of the shorter (vertically speaking) slides on other guns. The CZ, with slide in frame, was not viable for her.
Also, full-size guns, with larger slides (and more inertia to damp recoil) tend to have easier recoil springs to overcome.
Changing to a lighter caliber, in similar gun, can also help.
Good luck,
M