Oh Boy, this is a complicated and frustrating fight but in easy mode is very doable. I have several saved games but I don't know if your program would take them, maybe changing the name with the editor would do the trick. For the moment I'll try to find the youtube that gave me the idea how to avoid being killed, I was just jumping the wrong way. It doesn't need very quick fingers rather jump at the right moment in the right direction.
The important thing is for you to keep alive and go slowly in killing the reaper. HERE
there is somebody taking it very very slowly, you don't need to be THAT careful but you can. This is not the video that helped me but it may help you understand the mechanism for killing him.
Let me know if you are still stuck after this, I have been very busy and not come as often as normal in GameBoomers but you can send me an email, that I always read, and if at that moment I cannot send you a save I will let you know when.