How can I prevent relapse?

So over the years I developed a porn addiction, always looking for that more perfect view of the more perfect girl, spending hours just searching new things and all that.
Thanks to a relationship (that is now over though) I got myself away from porn.
She broke up 2 months ago and I managed not fapping to porn since then (only fapped once in between due to what seems to be called blue balls and now since I reached my personal goal of a month) (also only fapped to porn once during the relationship just to realize how "meh" it is) but thanks to an unfortunate ad I got reminded how "awesome" porn is (or more precisely looks).

I'm really happy that I got away from porn but I feel like I might go back there at some point... it's so tempting.
What do you recommend to stay away? Are there any good/better alternatives if I have the urge again? I've read that some people really like erotica texts.
I wanted to try to stick to my imagination but that might lead to my ex, which I really don't want...

Maybe amateur porn only? So I still have the visual stimuli but I won't end up looking for that 40kg girl doing splits while... You get the point

Another thing I'm wondering about: Since I got off porn I feel like I'm more into "chubby" girls. I started going to the gym this monday and when I look at the girls I think like "she got a great body, but yeah...". It's really weird for me. Maybe it's because my ex was rather chubby and I kind of miss her?

Sorry for that rather big and I guess "random" post. I'm new to this forum and quite new to NoFap... and confused