The answer depends on perspective and balance.
If you're wanting to decide to stay in a game or join a game, you should make your decision based on whether you will have fun. That's the ME answer.
If you're in a game, it's a given that YOU want to have fun. Who doesn't? But if you want to have fun in a game on a regular basis, you can't look at only what you want. You have to see what others want, and see if you can give them that, while you take what you want. If you can't do that, you're part of the problem of bad games.
That means from a group perspective, the answer is "Everyone"
However, some pigs are more equal than others, so you've got to consider who runs the circus. If you've achieved balance and everyone is having fun, you've got no problem. But if one person at the table is not having fun, the impact of that imbalance depends on the role that person plays. If that role is the GM, then the game is in trouble. They're in charge. They make the game happen. No GM, no game, no fun.
To sum up:
If you are continually NOT having fun, then make the ME decision and change the situation
If you're in a new group or ongoing, you need to make the Everyone decision, and make sure you give as much as you take
If you're in a group with problems, that you want to save, make the GM happy first, then circle back and make the players happy (you may not have as much work to do, once the DM is happy).
Oddly enough, all the ME solutions that don't involve leaving the group, involve making others happy, then reaping the benefits.
The point is, if you fixate on yourself, you'll tend to towards selfish solutions, that won't have a positive effect greater than yourself. If you recognize that working with healthy humans (non sociopaths), making them happy will cause them to reciprocate to you, you'll achieve greater positive effect, beyond your own self.
Basically, the healthiest way to make yourself happy is to focus on making others happy who will return the favor. (note the clause "who will return the favor", giving to takers just leaves you empty).