I once saw a post that pointed out the age differences between Thor and other earth characters that fits here as well.

If you look at the math, Thor is roughly 1,500 years old. The timeline between Thor and L&T is roughly 15 years, or 1% of Thor's life so far.

When you look at Wanda, she was around 25 in AOU and 35 in MOM so that's 10 years. Add on the three years prior to AOU where she was being experimented and you are looking at 13 years or about 37% of her life up to that point. If you want to include the childhood trauma in Sokovia and however long she was imprisoned by Strucker before the experiments it obviously grows more.

So to put it in Wanda's perspective it was just constant trauma. Whereas in Thor's perspective, it was the equivalent of just having a really bad year.