What you like when gambling alone/ with your friend? gamble with your friend or alone playing in your room/casino. i would like to play alone because i think i must concentrate when gamble.
First of all, It depends on type of the game.
Secondly, on how you play with it(through online or through real casinos).
If you play online then I believed It will be better to just play alone as you cannot enjoy at all playing with your friends while you are in a virtual world and in front of your computer.
If you are playing in a real or physical casino not the online or web hosted one, then that is more fun to play with your friends and colleagues.
But still it depends on the person but for me that is my answer to your question.