All-in?

Played a home game last week of no limit. When it got down to heads up, myself and a buddie I found myself tightening up even though I had about 2/3 of the chips. This is very unlike me as I'm normally aggressive, sometimes too much so! Anyway the buddie is a fairly conservative player so I found it a bit strange when the small stack was pushing me around.
A number of times he pushed all in on the button preflop and I folded even with one or two decent heads up hands(K10, A6). Eventually I found that he was passing me out in chips and getting a real head of steam. Next hand I was dealt 83 hearts. A put in a small raise and he called(not an all-in for the first time in a while). The flop came 8,6,4 rainbow. The buddy goes all in.
Now 2 questions:
Firstly, what would you do, and why?
And secondly, I hate going all in preflop, it becomes way too much of a coin flip. How do you deal with the strategy I faced without being dragged down to that level?
(OK OK I know that's 3 questions!)

He may have a gutshot straight on the flop, thought would be very brave to go all-in with that. He may also have slow played, a few things to think about here

Personally, I call the all in with top pair, despite the low kicker. If he has no PP, he could be drawing to a max of 12 outs, giving him a 25% chance of hitting (2 overcards and gutshot str)

I take the 3/1 odds and hope to take him out

1) If he's going all-in repeatedly, he's unlikely to have better than K 10, and highly unlikely to have better than A 6 so call.

2) Top pair H2H = no brainer call.

3) You've got no choice but to be "dragged down" to his level if he's going all-in all the time. If you sit and wait for hands better than K 10, A 6, and top pair post flop, he'll beat you - simple as that!. His strategy is a great "leveller" if he feels your a better player than him. You'll just have to pick a spot and take a stand - you've got no choice!

Just about anytime i get an ace heads up i'm putting the lot in.I'd have called the top pair too.

Heads up the aggressor wins, usually. You have been way to passive.

CALL!!!!! When are you going to push back, when you get AA? Top pair in heads up is about the best you can hope for on a flop. If he has an overpair, nice slowplay and he trapped you (doesn't seem to be his style). He has been the aggressor so far so I can't see him slowplaying anything.

You needed to be the one going all in preflop with the chip lead. You have to make him decide when his cards are not good, not the other way around. If that is the tatics he has employed against you, the only way to get him to stop is to fire back first and let him see if he likes his hole cards. Eventually you are going to have the huge hand all-in preflops the way he was playing.

Heres my opinion:

To begin with i don't like the "small raise" part, if your gonna try and steal with 83 then raise a decent amount and find out what you're up against, either that or flat call and hope to hit a peach. You probably would have found that situation a lot easier to deal with if you had flat called then checked the flop to see where you were.

Answer 1:

FOLD, It's easy, he could have any number of hands, a lot have you well beat. Any 8 with a bigger kicker, any 2 pair, any over pair, a set, a higher flush draw....... you get the idea. You're both even(ish) in chips, wait till a better spot.

Answer 2:

How to combat the all-in pre-flop stratagy? You can't, you can however limit you loses or at least reduce the times you have to make hard all-in calls. Play decent cards and use your position, dont make a small raise from early position with 83 trying to steal the blinds, the same applies to limping in with middle pocket pairs ( 7's, 8's ), an all-in behind you makes your call difficult.

It's a basic and very safe answer i know, with experience you'll make your own plays.

Good Luck!