There are some things that warrant us to be rightly angry and other times when our situation is disproportionate to the situation at hand.

Your anger is interfering with your life and hampering your mental well being.

Sometimes we can "fight" and sometimes we can "flight" - I think you're doing the latter when your anger arises in front of other people and then it lands up in a massive self explosion when you're alone.

You should consider getting professional assistance to guide you towards healthy ways of dealing with extremes of your emotions.

Be well.