How to combat these things?

It doesnt really need since you can do both things.It is just a matter of fund management.If you do tend to invest then you shouldnt touch those funds no matter what and since you allocate
budget for gambling then dont go beyond that and if that urge call to gamble is there then better to find another alternative or you shouldnt continue at all.
Learn to control yourself because if you dont then consequences would really be next in line.

Investment is investment and if you do really mind on making profits then you should lets your gambling activity would mixed out.