What sleep routines work for you?

We've hit the stay awake waaaaay past bedtime milestone. I know it's probably separation anxiety because he is still a decent sleeper through the night and can absolutely self soothe when he WANTS to. But he has started this last week to fight bedtime so much and just wants to play or be held or snuggle mostly with me. Whatever routine we had is just pointless since we do it and he now stays up for HOURS afterwards and will scream cry if put down in the crib.

So what is working for everyone else? I'm researching all I can but at this point I'm at a loss. I can't spend 3 hours a night putting him to bed.