"I'm trying to make life adjustments. A lot of people, when they go through treatment, they've able to make these adjustments in anonymity; I'm not and that makes it a lot more difficult."
Woods also shrugged off a Sports Illustrated survey which claimed that 24% of his fellow PGA Tour golfers suspect that he has used performance-enhancing substances.
"I've never taken performance-enhancing drugs, never taken HGH (human growth hormone), never taken any of that stuff, but everyone is entitled to their opinion," he said.
Woods also denied speculation that he had axed swing coach Hank Haney following his poor showing at Quail Hollow, saying: "I'm still working with him."
McIlroy will be among the favourites when he tees off at 1828 BST after shooting a stunning 62 to win at Quail Hollow, but the Northern Irishman said: "It was a great weekend and I played really, really well but this win doesn't mean I'm going to contend in the majors right away. I really hope I do, but it's a very long career.
"I feel pretty comfortable in that sort of environment. If I can learn something every time I play a major, by the time I'm 23, 24, I should be in a good position to go after them."
Meanwhile, Anthony Kim has joined Steve Stricker in pulling out of the tournament.
World number three Stricker withdrew on Monday because of the collarbone injury which also forced him to miss the Quail Hollow Championship.
Fellow American Kim, 11th in the world rankings and third at the Masters, has a long-term thumb problem.
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