This might be an impossible thing to accomplish, it's easier said than done. Personally a good reason for me to quit gambling is due to the negative effects it has. It doesn't matter if you win as long as you are constantly involved in it you will definitely lose everything you have won including the funds in your bank account. This makes me wonder, what's really the point of gambling and winning in the first place if you would still lose everything?
Losing in gambling can affect your temperament and also your relationship with other people, it can also lead to depression which is totally not a good feeling. Quitting isn't easy but if you can get it done make sure you do it.