It really is a scary thing when it happens.
Mine was similar to yours but with a diamond twin star coming towards me, but he wasnt far off of the same altitude as I was. That took a quick reaction and a few moments to compose ones self.
We were both trying to navigate around a thunder shower at the time.
About a month or so later 2 light aircraft collided at coventry (while I was flying) That broke my heart to see that all over the news.
Sad news and RIP.
I always hate reading about mid-airs. I came close to having one once a few years ago and I know how lucky I am to still be here.
My heart really does go out to them involved.