Sadness and guilt

My ex passed recently. We went through quite a lot of things together, and at the time I was in my early twenties. There is so many good and also some very not nice things I shoved to the back of my brain and didn’t process.
Finding about his passing has made me feel a rather mixed bag of emotions and I feel I have no one to talk about it too.
I feel guilty for feeling sad but we really did go through so much together. I know in my heart it wouldn’t have been good for our relationship to continue, and we did end up meeting up a few years ago, and there was no bad blood there.
I had a thought about them evening before he passed about them, which has scared me even more.
I feel very lonely, sad and guilty all at the same time.