These can be very different reasons. This will certainly differ from person to person. What is normal for one person may already be a sign that more than normal gambling is going on for another. If you enter an addiction phase, you should try to get out of it as quickly as possible. Write down the symptons.
Symptoms of gambling addiction:
1) Are you sure that there is a system that will allow you to win at gambling
2) Are you sure that certain actions of yours can increase your chances of winning at gambling
3) You constantly think about potential winnings
4) Heart palpitations and sweating
5) You don’t remember the last time you were sexually attracted to a girl
6) All your thoughts about gambling
7) You are not interested in ordinary life
8 ) Time passes faster than before
9) You see gambling as a source of income
10) you dream to win back