It sounds like the padding has broken down over years of use. There isn't much you can do for that without recovering.

If you can't re-pad (re-stuff) the chair, then what you could do-and it is not the prettiest way to resolve the frame coming through-is to add pillows as a barrier between you and the frame. Sometimes furniture just wears out and needs to be replaced.

Another way is to have someone professionally re-upholster it.

Can you open up the upholstery on the back side someplace and add stuffing?

Betty would it be possible to put on a slip cover?

https://www.hometalk.com/9447770/reuphosltered-armchair?expand_all_questions=1

https://www.hometalk.com/3635957/rocking-chair-redo?expand_all_questions=1

https://www.facebook.com/Hometalk/videos/2318857635084476/

Midnight Sky and Toile Chair

Rocking chair redo

I've used this tactic...it may work for you: exquisitelyunremarkable.com/2015/07/custom-upholstered-chair-easy-diy.html

Hello. Could you post a picture of your chair? More information might be able to give more specific suggestions or potential solutions knowing the style and general shape of the chair. A slip cover might be something to consider.