Despite what some may think, this section is probably the most vital thing I am going to write in this entire essay and it is much more than the generic sentiment that games should be fun. If you do not have fun playing mafia you should not play it not only because games should not tax you, but also because you will be a much poorer player because of it. When you do things out of obligation instead of zeal it will hinder what can reasonably be expected from you. People too often do not realize this and attempt to play in poor circumstances when really they would have been better served simply taking a break and coming back when they were better able to handle the workload that a high paced mafia game can put on a person from time to time.
In game this remains true. Frustration at times is to be expected if things are not unfolding in a manner which you would like, but allowing it to override your enjoyment of the game continuously is going to do nothing but harm the decision making paradigm you implement. Sustained stress and emotional volatility lead to lapses in judgment and in a game as competitive as mafia that can lead to unforced errors which will inevitably lead to just more stress. Nip it in the bud, and remember by having fun you contribute to a more welcoming environment as well as a better played game over