Trump

The democrats just hate Donald Trump with all their hearts because his whole shtick was to not conform to the regular political expectations. During his campaign he was always making controversial statements strongly and he was not apologising for them, which resonated with a lot of right wingers who felt that their ideas were no longer allowed a platform. However, this of course had the opposite effect on left wingers and the country has gotten more and more polarised since.

I personally think that Trump has been giving up too much ground to the democrats during his presidency in the hopes that this will appease more democrat voters, but he doesn't realise that the democrats will keep asking for more and more and will still hate him even when he makes compromises. An example of this is the recent executive order that Trump signed to end the migrant family separation at the borders. Family separation happens for a perfectly good reason at the border and it keeps children safe by removing them from potential dangerous jail/prison environments. Trump could have easily made an argument against the democrats on this issue but decided to concede instead, and if you read recent articles on the matter, they are still nowhere near happy. He gained no voters from this move but further upset his base of supporters who expected him to stay strong on issues like this, and this case is just one of many examples.