"In order to live, you must be willing to die" -Amir Vahedi

Jonah, what you have here in not a "card" problem, its a math problem and once you begin to see it that way your course of action becomes a little clearer. You don't need "the Nuts" to beat this guy, you need brass nuts and the confidence that you are making the mathematically correct choice.

You didn't give the details of when he was going all-in, so I am going to try to give you answers for a few different scenarios; choose the one which best fits your situation.

1) The player goes all in Pre-Flop:
a) Every single hand - Every time they place 2 cards in front of this guy he screams "all-in". This has got to be frustrating to you and the other players in your game (that is a huge part of the appeal to him). You need to look at this situation like you are playing him heads-up. If you wait for a premium pair you may wind up giving him 50 or more Blinds and by that time only be able to make a dent in his huge stack when you put him (or call him) all-in. Even with a premium pair, you are going to lose nearly 2 in 10 of these challenges. Your strategy should be to pick a hand that has a better than 50-50 chance of winning (Q7s and up) and go for it! Or if you feel more comfortable, pick a hand that has a higher percentage like 60% {5's and up, suited A's 7 and up or unsuited A's 9 and up, suited Q's and K's 10 and up, or unsuited KT and up}. Here you will lose sometimes, but in the long run you are making the mathematically correct choice and it will pay off.
b) He only goes in "some" of the time - Here he is playing the table heads up and has picked his percentage (what he is comfortable going all-in with). Here you need to find out what % he is playing and go one step more conservative. (Trust me, if this guy is as OCD as you say he is, he probably has the percentages of every pair against a random pair memorized.) If he is playing 55%'s, them you should be only playing 60%'s and up.

Yes, you are going to lose some of these hands, but that's Poker; you have to be willing to die if you want to live.

2) He is going all-in post flop.
a) After every flop- OK, so this is going to sound counter-intuitive, but in this situation you want to challenge him NOT when you have a made hand, but when you have a good drawing hand. Example: You have AcAd and and he has JT of spades, the flop comes Ah, 9s, Qs. You have a "made" hand; 3 aces. The odds of you improving to Quads is astronomical, but look at his hand, he has 15 outs!!! He is going to improve to a straight, flush or a straight flush more than half the time in this situation. Here, he can beat your "made" hand because he has the drawing odds in his favor. So if he wants to go all in post flop on you, call him if you have 14 outs or more. You may not win every hand, but the odds will be with you and eventually you'll win.
b)If he is only going in post flop some of the time it is because he is looking for ideal number of outs before he goes all-in. What you need to do here is to bet your good hands HEAVILY before the flop. The flop is going to miss him 2 out of every 3 times so when he folds to your pot sized bet after he has missed the flop, you have taken a nice little chip dent out of his armor. Get as many chips as you can in the pot before the flop and see what happens. If he goes all-in, call him when you have the right number of outs.

Poker is all about the numbers and even when you make the right choices, you are going to lose some hands. In the long run you will come out the winner. Think of it as a long term game over many, many years. Don't focus in on it from hand to hand, but over a long period of time and thousands upon thousands of hands. Play the right percentages and you'll come out the winner.

I am also going to give you a little psychological advice, absolutely FREE! This guy is a bully and there is only one way to deal with a bully. PUNCH HIM IN THE MOUTH! (Poker-wise, I am not advocating violence.) You have to let this guy know who's boss! As long as you lay down to this guy and give him your lunch money, he's going to keep taking it. Show him that you are a much better poker player! Stand up to a bully and you'll throw him off of his game. Put him all-in and see how he reacts. Pick a time when you are in good mathematical position and stand up to him.

Yea, I know, you are going to take some bad beats from time to time and you are going to be in and out of some tournaments rather quickly, but you can't just sit there and let this guy steal from you! Good players take more bad beats than bad players, because good players are playing mathematically and fundamentally sound poker while the other players are getting lucky from time to time. If you made the right play and got knocked out of the tourney, then so be it. Don't beat yourself up about it psychologiaclly. That will happen from time to time (remember that 7,2u will beat AA one in 10 tries). You will be a winning poker player in the long run if you play the proper poker percentages; even if you have to take a bad beat from time to time.

And there is also a bonus to standing up to this guy. Once you knock him out of the tourney you're going to look around the table and see all eyes on you; thankful that you knocked that guy out and fearful because now you are the big bully. Good luck!

May the flop be with you,

Ghost