Political parties aren't families or sports teams, and people aren't traitors for leaving if there's a failure of ethics and/or accountability. The attitude that you vote with a particular brand no matter what is how the USA has ended up with a two-party system and unpopular candidates. Democracy is supposed to be rule by the people via elected officials that actually represent them.
Both major parties are getting really nervous about losing support, and as a result they're getting very aggressive. Republicans have their RINO label (Republican In Name Only) to shame people, and now that attitude is appearing on the other side in response to Democrat fears about the next election. I REALLY don't want to see Trump re-elected - I don't think he should even be allowed to run given his recent insurrectionist/criminal activities. But I also don't want any politician to be so comfortable that they feel they can do whatever they want and keep power.