That seems to be a bit of an over generalization that all legends quit if they are losing. I play for fun and the result is immaterial providing the people I play with are friendly. I have never willingly quit a game because I am losing - and I am just an average player.
You have been at TM for a long time, perhaps you should concentrate on pushing to make legend rather than just getting your CDB or alternatively just play MP with your own tier if you are worried about getting tiered up.
Edit - why are you wanting to play legends? I can assume you want to get tiered up but all your stats point to the fact you are not ready. In particular 25% sand saves, 32% scrambling and 1,91 ave putts per hole?
In hindsight, just practice!!!