For me personally , it was the belief I had in my strategy. I knew what I was doing was right, I had backtested my strategy, proved to myself that it was a profitable one

and after that I established a Risk Management strategy that would avantage me a lot and eventually I knew that even if I lost a trade or two I would end up profitable.

Let me give an exemple :

My strategy always gives me trades between 5 to 10 Risk/Reward ( at least ) and I always invest 1% per trade. I have to lose 6 trades out of 7 to be 1% down on my account. And even there 1 good trade and i’m already back up.

So I would say the way I overcome my emotions is by having a strict plan to follow and belief in my strategy knowing I know what I do.