If your state elected Trump by its popular vote, it’s your responsibility to vote for him as someone who is allegedly representing the people who voted for him.
It’s not YOUR personal choice.
If that were the case, then why even bother with the election? Why not just have the electors decide who’s going to be president and avoid the whole election year mess?
He resigned so it’s not his responsibility anymore. The RNC will pick someone else to perform this duty.
Representation is a fire break against the evil that can burn over a pure democracy. Without the EC, Trump would have lost. Resignation is always an option, but it does not take a lot of imagination or examples from history to see how an elector might need to self sacraficially defy the will of the people.