My train of logic is that of a pragmatist with an idea of getting the best done under the circumstances, rather than a spoiled child who throws all the toys out of the pram because he can't get his own way.Yes actually. If a political party is clearly not actually interested in supporting your cause then why continue to support that party? In regards to the environment they have shown through their actions that they do not care. Your train of logic is the same as that of an abuse victim that continues to stay with their partner.
The Republicans have factions with competing interests too. They just knuckle down and back the party. The membership stuck up a massive twat like Donald Trump as choice, and the voters dutifully put him into power anyway. I mean, just about the only way a Republican can really blow it is to have an uncomfortable interest in underage girls.
If any of the factions of the Democrats want to get anywhere, they have to understand that they need an alliance with all the other factions, and that means those other factions are likely to water down each others' agendas. The alternative is that they condemn themselves to something worse every election, and sit around in mutual recrimination all demanding the other factions surrender their objectives until the Republicans turn the USA into Mad Max.