i suggest focusing on finding your muze, then going back to commissions. do a barrage of inspirational stuff, then or music, or anime,or what ever is your key. then go back to th art once you reset your head. :p

Take a break and play a couple video games or watch a movie. Allowing your creative side to rest might do you some good.

keep at it... slowly.
you'd get there.

WHAT EVERYONE ELSE SUGGESTED. PLAY A FEW GAMES. READ SOME MANGA OR SOMETHING. MAYBE SOME COMICS ONLINE.

Why do you have to refund the commissions?

Just let the people know who have to wait, then see who's cool about it. If they're cool about it, don't worry about them and you can do them later. Do some sketches for them or something to make up for it if you feel that guilty.

Go for a long walk, then dig into burning out commissions if that's your main income. If you've got another way to raise the cash, do that and give yourself some time to un-burnout.

Hey man, chill....

If you have to make refunds (which sounds like your customers wanted a refund/backed out of the commissions), I suggest powering through the commission list you have then taking a break once finished, however long you think you may need. First day of your break, note/email your refund commissioners, let them know on such and such date that you will be opening commissions and thus will get paid and be able to refund their money then but not until that date. When the date rolls around, open up commission slots, just enough to repay the refunds (to keep from getting bogged down again and ruining your muse's recharge).

Once the slots are filled (do not hold slots for payment later than 24 hours to insure you get the money together), note/email your refund commissions about the incoming money and repay the refunded commissions immediately. Power through these slots, get them done quick. Now you are able to make some money for yourself or take a longer break if you are financially able.

Pace yourself, you are too talented to let yourself get severely burned out. Work on what you want to work on. You have a following, sometimes when creating more commission slots, theme them to a subject you are interested at the time example: "Alright guys, I'm really feeling a need for some dirty apes or smurf tame art, who wants a commission of these?"

Thats a very wise reply and i would if he does this

pretty much the same thing everyone else said, do the commissions you have in your list with time, dont rush.
and after that, take break and do what you like to do.
dont worry dude

Uhhh.. try doing what you love? Or spending soem time just chilling out.

sounds fuck up. Cuerpomatic?

Go rub one out, watch a movie, sketch something totally stupid just for yourself ... and then see how you feel ^_^

Just take it easy and take some chill time. Maybe watch a film/ anime/ play some games, what have you. Get back into your groove. There is no need to rush so just take your time and find your muse. If you want a good movie to relax and laugh to I recommend Trains, Planes and Automobiles. Very funny.