i had mono over 16 years ago and had so many of the problems you all describe for over a year. bad news: my immune system has been out of whack since. good news: you can beat it and have a good life. i've written here what i wish i knew 16 years ago.
since some of you aren't getting good info from your drs, here's some background on epstein barr virus. EBV is actually the virus that causes mono. mono is an acute reaction to it. but 99% of people have been exposed to this virus by the time they're adults. when exposed for the first time as a child, the reaction is usually mild. but the older you are when first exposed, or if your immune system has some innate vulnerability, the harder it'll hit you. some people can develop autoimmune hepatitis during acute mono.
for those of you who find mono lingers past a month or so, i have some advice.
1: take a leave of absence from your job, school, etc., for six months, find someone who loves you, and let them care for you so your body can heal. if you have a parent who can do this, great. otherwise, turn to a friend. if you can't have someone care for you, and i know that's not always possible, do your best to never push yourself: eat well, sleep well, meditate, get light exercise but not much, practice reading (it helps with the neurological symptoms) but don't push yourself.
2: THIS IS KEY: i don't normally advocate for medications, but go to your doctor and ask to be put on a trial of tricyclic antidepressants, such as imipramine, for a short while to help you recover. they are relatively safe (older and more researched than the newer SSRIs), but do have some mild side effects. the key with them is they both work on depression and promote deep sleep. if you can't tolerate these, or don't have a doctor, try Benadryl, which is an allergy medication. it's also relatively safe, non-addicting, and the important thing is if you take one Benadryl (two if you're a bigger person) at bedtime, it should help you to sleep. this is the key for feeling better with chronic post-mono symptoms. i was on imipramine for two years, then have only used Benadryl since when i have a minor relapse brought on by stressful events.
3: take a good vitamin. i like Just Once by Rainbow Naturals, you can find that at the health food stores. drink kefir. Nancy's kefir is amazing and non-alcoholic. it will help your immune system. make sure to eat fiber with it; apples are best, they have the kind of fiber that the probiotics need for digestion. otherwise, don't worry too much about supplements. you can waste a lot of money on those and not have appreciable effects. not saying they aren't useful in some conditions, but EBV is a different deal. also some of them (echinecia being an example) are not good to take for long, especially if you have something like EBV--they can overactivate your immune system if used improperly and cause problems long-term.
4: get off the Internet. go have some fun (rent a movie, since that's about all you can do with mono) with a friend, etc. read a book. meditate. anything is more relaxing than thinking about your illness. you need to have a reason to want to be engaged in life again.
5: make your home somewhere really pleasant and happy to stay. add a reading corner with some plants and a lamp with a full-spectrum lightbulb, the kind they use in Norway. this will help with your mood and give you a good place to recover.
5: when you're feeling better, sign up for a good exercise class that combines exercise with meditation and/or stretching, such as yoga, pilates, tai chi etc.
6: if you are having severe problems, please do get checked out for autoimmune issues, since mono/EBV is associated with these. a rheumatologist will give you a lot of standard bloodwork, but remember to ask for a full panel, not just the standard two, of antiphospholipid antibodies as well.