[Paradox] wrote:-snip-
i'm so sorry for your loss ):
i don't know if this is reassuring to you in any way, but i had a very similar cancer experience with my golden retriever, who passed away at 6 years old in 2018. we went to the vet for months before they finally found it was cancer, by which time it was too late.
i don't think this is an uncommon thing at all for pet owners. the fact that there's at least two of us with similar stories on a niche pet forum probably says enough. and you're right in that it does hurt so much more than when our pets live long lives and die a more natural death. i blamed myself as well, and still do. i would tell you not to blame yourself, and that you couldn't have known or changed the outcome, but i know that me saying that probably doesn't help at all.
i honestly can't recommend anything to make the pain easier, because nothing did for me. i hope you're able to eventually look back at your good memories with her and enjoy those. i hope that with time, your pain gets easier to manage. sending lots of love your way and if u ever want to talk, my pms are open!