What you do is keep your cool. Playing heads up poker, Aces lose 20 cent of the time, and the more people in the pot the higher your chances of losing. Just saying, your gonna lose with Aces too sometimes. If you raised $30 in $2 blind, a keen observer might have noticed that that play makes little sense, put you on aces, and new he could take you for everything if he hits a big hand. And thats what happened. It's poker. We all have to take losses in this game. The key is to keep your composure and stick to your discipline
This in my humble opinion is the the wisest of the recommendations posted thus far. To expand on this a couple things additional to consider..
We're you having a good, average, or terrible session at that table before this hand? Then how about your opponent?
Up big, new to table, or down a ton?
I know those don't seem like normal questions but here's the logic behind it. First off a $30 raise here just smells like scared money to me? It just has that I'm going win this one dammit vibe.
Second people who call those types of raises with king ten are one of three types.
Sharks that smell blood
Lucky fish on a really good run
Or people who you won't be seeing much of because their broke!
So the next time you sit at a table consider that? If that guy has 200/250 bigs and table max is say $100 buy in he's hitting cards. Some times on some days people just can't be beat no matter what your holding.
Finally if your this upset over getting beat with bullets and you were the aggressor who placed this large preflop bet? You need to just stop completely for at least a week! No poker none no tournaments no
freerolls and absolutely no more cash games! Go fishing or something but step away from it and clear your head and your frustrations. Or get used to going to the ATM often! Been there done that.