I don’t have any experience with the Ruger, but I do have experience with the S&W .380 EZ. I liked the EZ when it first was introduced, but not as much anymore. It is easy to rack and the magazines are easy to load. There are downsides. It is a single action gun with an internal hammer. If you don’t get one with, and use, the manual safety, depressing the grip safety turns it into a single action gun in the holster before you draw. Then there is the grip safety itself. The pivot point is toward the bottom of the grip and not the top like a 1911. That means if you relax the grip near the tang, it can relax the safety to the point where it will not fire when you pull the trigger. Also, unlike a 1911, the gun will then not fire if the trigger is held back and you then press the grip safety hard enough. You have to totally let off the trigger with the grip safety depressed and then pull the trigger again before it will fire. I have an acquaintance who is a police firearms instructor, USPSA competitor, and a CCW teacher. This may not apply to you, but he sees a lot of problems with women in his courses who either fail to grip the safety on the draw or eventually relax the grip during strings of fire, resulting in failures to fire. This quote may be an example of this:
My sister had issues with the grip safety on the S&W
I will say that my wife likes the gun. But, she likes it because it is light and easy to carry and not because of grip strength issues.
I really like the Glock 42 and the Sig P365-380. The Glock really needs a good break-in and may not be great for someone with hand strength issues. The Sig also needs some break-in, but I think to a lesser extent. The magazines on the Sig are difficult to load to capacity even with the supplied loading tool, so you may need someone to load them for you if hand strength is an issue.
I really would want to shoot them before buying something.
As an aside, if hand strength was an issue with my dominant hand, and a doctor recommended limiting recoil, I think I first would try to see what I could make-do using my support hand to shoot, whether I tried a new gun or my current carry firearms. That’s what I did when I broke my wrist of my dominant hand many years ago. By the time I recovered, I even was writing well with the support hand.
I hope you get it figured out satisfactorily.