It therefore came as a shock to me that most Jews consider Poles their enemies and pretty much Hitler's collaborators. Needless to say us Poles feel very hurt by this attitude.

I've seen this trope ("Jews consider Poles their enemies, even though we tried to save them!"), but I've never actually seen it. I mean, it's not like there are Jews out there writing odes to Poles or anything, but Poles specifically as an enemy isn't really a thing. I mean, Eastern European Christians in general maybe, but I've never seen any anti-Polish enmity outside of Poles complaining about it existing.

Anyway:

I'm natively Polish and was always taught in school that Poles did everything to save the Jews despite being threatened death of their entire family for doing so.

This is pretty whitewash-y. First, it's important to note that a huge number of Poles did protect Jews. Yad vaShem's "Righteous Among the Nations" list has more Poles than any other nationality (though the Netherlands has more per capita. The famous Danish fishermen who saved virtually all the Jews of Denmark are actually ineligible, since they were paid, though the organizers of it are listed).

However, often in Polish circles the extent of it is exaggerated. The Polish resistance did at times attempt to save Jews, but it usually wasn't a priority. Part of the issue was that it was more difficult than other forms of resistance--it's hard to melt into the woods with a trainload of Jews, many of whom would be aged, young, or infirm. Sometimes post-war Polish sources express a bizarre near-ambivalence to rescuing Jews--sort of a "we would've rescued them if they'd been willing to fight", implying that it's reasonable to assume that a random sample of Jews (few of whom will be able-bodied young men) will be able and prepared to resist (specificially regarding attacking the transports--apparently it was attempted once, the Jews did not overpower the German guards, and it was not attempted again). Or writing how the resistance would've joined in the Warsaw Ghetto Uprising, if it'd come at a more strategic time for the Polish resistance (which it couldn't've, the revolt began when the Ghetto was liquidated, there would've been no one alive to fight).

So while lots of Poles did attempt to save Jews at risk to themselves and their families, it's not as though Poland was united in a vast effort to save them. Jewish resistance and uprisings happened mostly separately from the Polish resistance.

Were Poles particularly antisemitic before and during World War II? Any worse than other (non Axis) European nations?

Before WW2, Poland was pretty antisemitic. In the 1930s, for instance, youth nationalist movements had advocated for "ghetto benches", so Jews couldn't sit with Poles in university classrooms, following growing violence against Jewish university students. Which given the rising tide of antisemitism in Europe, wasn't exactly shocking, but antisemitism did certainly exist in Polish society. It's certainly different than American university antisemitism of the era, which was limited to quotas (which were sometimes only subtly enforced)--Poland didn't have university quotas at all for several years after WW1, but they returned.

During the war, a great deal of the Holocaust was perpetrated and assisted by local collaborators. However, this was much more common in other countries, like Ukraine and Lithuania, than in Poland.

And after the war, there were incidents of antisemitic violence among Poles. The most famous is the Kielce Pogrom. These effectively ensured that survivors would not return, barring any chance at a revival of Jewish life in Eastern Europe post-war.

On this subject, I would highly recommend Antony Polonsky's My Brother's Keeper: Recent Polish Debates on the Holocaust, which is a discussion of essays/articles/etc which were written in the 80s when a flurry of debates/discussions on this subject in Poland occurred.