You have a chance to start the process of internal and external repair. You can start this by not lording your victory over your fellow American.
Do not impeach Trump. Let him dig his own grave for the next two years. Don't make him a martyr. He'll trash what's left of his legacy on his own.
Limit your investigations for now. Put whatever brakes you can on the bad ideas, but don't gum up the workings of politics only through retribution. That's his job, and look where it's taking him.
Don't ignore what the opposition tables. If you can find any common ground - any of it - take it. This is how you cement those flipped seats. They were staunchly republican for a reason, and their current state is an aberration. If you try to plaster the Democratic agenda all over it, you'll lose it in 2028.
In short, the counter to the far right Is not the left, it's the middle.