I know exactly what you are talking about. its addiction to dopamine reward receptors in the brain that causes impulse control disorder. Chess activates the brain's reward system in much the same way that a drug does, so opposed as many says here its definitely not easy to overcome this. but you are not lost cause, because you are able to acknowledge your behavior changes, and that's big. when you win very nice game, you rewarded with dopamine, which in turn causes to be happy and cheerful about everything around you, and when you loose badly (on tilt), like a junkie without your drug, you involuntary become grumpy and nasty for no reason, trying to get that win(drug) at any cost, but playing much worse and impatiently, which in turn worsens things. i know this feeling very well...
Aggression

Stop playing very fast game and think very carefully on each move that you make and that your opponent make! And start to do something that make you feel good and in control outside the game of chess.
It could be to get in shape by walking 1 hour a day if you enjoy it like i do every second day and do some light training every other day or to eat better food (avoid all industrial processed food) and get lean and proud of your self or to get some quality time with someone you really like or with a pet....all of those will make you happy and confident....and chess will become less important.

@Marie-AnneLiz
Well said...
I really need a life. I sadly don't despite being a graduate with a B.Sc(H) Physics and currently doing a masters in physics.
I do play music but generally dissatisfied with it.
So, I need get into exercise despite constant struggles with it.

focus on 'improving' & not 'winning':
searching for the best plan is a fun way to play;
clean eating, exercise, lots of water & sleep...
nothing beats stress like petting a purring cat!

@Marie-AnneLiz
Well said...
I really need a life. I sadly don't despite being a graduate with a B.Sc(H) Physics and currently doing a masters in physics.
I do play music but generally dissatisfied with it.
So, I need get into exercise despite constant struggles with it.
Do something with a goal that you will enjoy (for me it was skiing) ,you can do light exercice just to get very strong abs and some for your legs(no need to go in a gym) and you will Feel your muscles strength and that will make you psychologically happier about yourself.
I talked about food because i was overweight so by changing my diet i lost a lot of fat and i can feel a lot stronger psychologically because i succeeded.
There are many ways to feel a lot better about our self....but getting in better shape and loosing weight are the two easiest one that i know that worked for me.
Good luck.

Just remember we all suck at chess and will never make money playing it so after accepting that truth you can let go of the anger and just play the damn game

Just remember we all suck at chess and will never make money playing it so after accepting that truth you can let go of the anger and just play the damn game
Yeah, I needed that.
Well, I am planning to take a break.
And improve my self.

OK
Just lost a few games!
I am still enraged, depressed, hopeless, useless despite taking a break and revising some stuff.
Guess I suck. Guess I cannot do anything.
I tried to do some exercise and play music, hasn't done anything.
I wished I ended myself a while ago.
Would resolve everything.
You want to get in "the zone", then you are somewhat outside of your ego and just play, without getting emotionally involved. Don't be angry when you lose and don't let a good win go to your head either.

I try to come out of this by moving on to next game very quickly. I will try to find one win and then take a break..
I think it's better to just take it lightly if you lose a game, as @claralively mentioned above, it's just a game after all. Perhaps you could watch YouTube videos to improve your positions? Usually when I start losing I would do that and learn new gambits or tactics to counterattack my weaknesses. I really hope you will win more games! Best of luck buddy!
same here