i thin you should not quit trading, you need to change your strategy about bitcoin, actually winning and loosing is the part of trading but you must be strong hearted not to lose heart.
I am also with you, i feel very sad when someone say that he quit trading. Because as you said losing and winning is a part of trading and also life, we should trust on self and do hard working than definitely, we can achieve everything.
In this world nothing is impossible, only determined yourself and do work properly, both things make your life easy, so same situation is here in trading, trading is not difficult it need time and knowledge.
It's not sad at all. It's called self protection. If you keep losing and losing without any improvements in sight, then the best option is to quit. It's that simple. It's better than someone continuing with trading and making even more losses. Some people just aren't made for trading.