If you are a professional poker player, it is quite possible that you will have a long session of losing your money, which means you can lose it for more than a day, week or even month. So you need to have a large bankroll for the poker tables that you can afford to lose and that will not affect your regular life at any cost.
It happens to anyone that even though he is a regular and good player, he might go on losing for some time. You will have to judge this for yourself because if your limit of losses is crossed, you should stop playing for some time. Take a break and come after some time to play at the poker table.
There are few strategies for playing the game and others are to be used while playing the game. Also you are the best judge for what you should do and what not, regarding money investment and losses. Every player has his own limitations and you cannot behave like a gambler on the poker table and lose the money, which could have been used for the betterment of your family.