I don't journal, but I have heard extensively about its benefits.
I will add that It depends on how you use it, because there are different ways to approach it. I'd like to recommend a couple of them.
I really like the idea of feelings collages. If you've never heard of them, feelings collages take a feeling word, put it in the middle, and follow it up with quotes/colours/pictures/whatever you associate with that emotion. It helps you process and recognise your emotions a bit better, and the act of putting them together may be cathartic.
Journaling also helps you break down an issue. I find it really comforting, when I'm overwhelmed, to watch videos that are really methodically put-together or well structured. That sounds so weird, but when you are going through a gooey mess of problems, it's nice to see someone identify steps or look at the big picture of an issue. Write it out like you would write a textbook. How would you suggest someone cope with how they're feeling?
Thank you so much for writing in, and I'm really glad journaling has already helped you so much.
DISCLAIMER: I would like to point out that sometimes journaling can make things worse, because you tend to think about it more, and you could get caught in thought cycles. By all means, try it out, but stop as soon as it starts to hurt.