I poisoned my cat..

Yesterday was my gf's birthday. I bought her Lilies... didn't recall it's poisonous to cats
This morning my gf saw vomit on the floor and she didn't know lilies are poisonous to cats as well
Until about 6pm I saw some pedals were chewed off so I asked my gf if the cat has eaten some of the plant
She told me yes and he puked
I thought it's strange he puked immediately after ingesting it, then I recall I read something about lilies and cats
So I checked online and found out lilies are very deadly to cats
We called the Animal ER immediately and drove him to the ER
The vet said the prognosis is guarded.. it may cause his kidneys to fail very quickly..
The vet recommended to put him on IV and monitor him for 48-72 hours to see how he's doing then we'll see what's the next step
I got home and read more online.. everywhere says lilies are very deadly even in very small amount, it could cause kidney failure in 1-3 days and cats who ingested lilies could die within 5 days

I kept blaming myself for being so ignorant and negligent
My gf told me it's not my fault and this is poisonous to myself..
I'm now switching from being rational and emtional..
Rationally I kind of know I can't control everything and I didn't know any better
But emtionally I feel like I'm responsible.. I feel like I should have done better and I should be smarter than this
I feel so guilty..

((((((((((((((((yellowm)))))))))))))))) I'm so sorry! Please don't blame yourself, you didn't know. I hope your cat will be ok.

well don't worry it will ok hurry i will like to say that you do really love to it so your real love make it get well soon.

Aw man, I'm sorry, that's a horrible situation. I hope the cat will be OK.

You didn't know... it wasn't malicious. Try not to blame yourself toooo much.