I don't like them either, except sedate roundabouts (proper ones with horses going up and down) and the kind of roller-coasters you can take infant DGC on. Why would you want to overcome your fear? As Baggs says, it isn't compulsory to go on rides!
I did like rides as a kid but now I just don’t bother, not my thing now. So if I can say no thanks, so can you, if you really want to prove it to yourself that you can “do it “ take a sea sickness tablet first, at least you are not likely to be sick.
Why do you have to overcome fear of rides? I can't stand them too not just now but when I was a youngster. Quite happy to refuse an invitation, happy to never set foot on one again!
Why do you need to get over your fear of rides? Why not just accept it and decide not to go on rides? Going on rides is not compulsory. End of problem.
I think you started another thread about your possible mental health problems could you not mention this in that thread Do you think this might be the wrong question to ask here ?