Sci-fi trilogy I read in 1980 or 1981?

It was about a man who moved from one place to another back and forth at will. It starts in our country USA and moves to another dimension This other dimension had people l who lived in forests and everything was concentrated on wood; another was water. where everything was concentrated on that element.There was always a woman in these other dimensions, different ones in each ; sometime in a love situation somethimes just friendship. I think there was a sicness or injury in the first book in the first dimension and a woman brings him back to health. There were wars he was involved in against other factions living in these dimensions. The main character would start in the USA and be transported to another dimension and then back again. I read the first two books in the early 1980's ('80 and '81).Sci-fi trilogy I read in 1980 or 1981?
The Chronicles of Thomas Covenant the Unbeliever By Stephen R Donaldson





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