You have to understand two things, which I have unfortunately had to learn from many long years living in occupied territory, ie DC. First, liberals' lives are entirely consumed by politics. This is why they are so quick to take offense or see racism or whatever in what normal people regard as everyday interactions. With them, it is all politics all the time.
Second, many, indeed most, of them are liberals because they are resentful, envious or embittered about something. They bitterly resent people who make more money than they do, unless they inherited it or are celebrities, then it seems to be ok. They are resentful of successful, well-adjusted people, particularly families, because it underscores their own failures. They try to pretend their bitterness is outrage at unfairness, inequality, etc which justifies their increasing obsession with personalizing even the tiniest disagreement.
There is a distressing, indeed frightening, mob quality to liberals/democrats. Every issue is a morality play rather than an honest disagreement between reasonable people with differing priorities. The democrat base are very easy to manipulate. We saw that with Colbert's audience the other night when they cheered Comey's dismissal before being lectured that they were to be aghast at it. Of course they quickly got on message. After all, Trump is satan.