Personally I play on Pokerstars, I can buy-in for as much as $5.50 a game but usually I play a lot lower levels, I don't intend to make money from Poker it just happens that if I am winning, the money follows but it is not my driving desire to make money, for me Poker is a fun and enjoyable pastime, and I only play to support my hobby.
My main rule of thumb is never to buy in for more than 1% of your total bankroll, and sticking to that rule I went from Free-rolls into 25 Cent buy-ins then on to 50 Cent, $1.00 Dollar games and so on, now as I say I could buy-in for $5.50 and still be within the 1% rule, but I am happy playing for lower stakes.
On-line Poker is just practice for me, for when I play live games in Pubs and
casinos, Live Casino games are different in that I can hold my own when playing in a live game, and buy-in for a lot more but again I don't need to make money, I play for the pure pleasure the game gives me.
The important thing to remember is to play with money you don't need, and can afford to lose, then Poker does not become a problem, because 80% of the time you will lose, it's a fact of life, and even the best players in the World will have losing streaks.
When the fun Stops, STOP!