Is emotional stability the most important trait when choosing a partner?

Last night, my boyfriend and I argued. I was very angry, so I left home and stayed at a hotel.

The reason for the argument was very simple. He looks for tart cherry juice to prepare for the trail race the day after tomorrow. Because all kinds of supplements are placed together, it’s not very easy to find.

I just ask, "Have you found it?"

He suddenly shouts at me, "I should’ve finished it by now!"

I was very shocked! I haven't done anything wrong and shouldn't be treated this way.

This has happened many times before. We are planning to get married next month. Tbh, Except for his emotional instability, he’s great in every other way.

What should I do? Are there any ways to resolve this? His emotional issues are really confusing to me.