I'm questioning what's gonna get better with time. Maybe he's been out from very hard physical training for so long that the body backfires on him because of that and not because of the mono.
Just thinking on myself after every winter doing the first long running pass I'm like I'm gonna puke and the day after you feel horrible too. For an elite athelete that's been out as long as Robin and where "training" means ELITE TRAINING then it's probably like that but times 10.
Question is if he's sure his fatigue is really mono-related or could it be that his body says no for other reasons? If so maybe he could work through it and hit a plateau when it starts to get better much faster instead of the very slow progress he has now. He will no doubt pay a terrible prize in pain and sweat but maybe it would actually work to "shock" the body into full recovery
What's left to lose? If he gets a new mono outbreak and has to be in bed again for months then he knows it's over and that he must aim for something else, like signing up for a university course or whatever. At least he gets an answer.
Now he's walking around praying that time will solve his problems. That only moves him and his body even further away from the hard training his body was once used to. If he means he already tried serious attempts and gotten so sick everytime he was back at square one then he should have already given up months ago.
Soderling is starting to remind me now of another famous Swedish athlete named Peter Forsberg that had a chronic footproblem but refused to give up his career. He saw so many experts in so many countries and literally tried everything and even the doctors were clueless eventually. Sometimes the stubborn players reaches a state where they only trick themselves but their love and passion for the sport is so big that they refuse to give up. Robin is not there yet but it's getting there