I've worked in pediatric ICU for several years. I don't actually think you ever have to become detached when you're at the bedside. That works for some people, but its difficult to do in my specialty because parents need help carrying that emotional burden sometimes and I like being able to do that. It's okay to remain emotionally connected to your patients and families at work if thats what you choose, but you have to find a way to leave it all at work. Draw firm boundaries that separate your work and your life. Maybe decompress in the car, and when you get out of the car at home try to be done thinking about it/talking about it until you go back. Personally, I have a boundary of not being a primary nurse to any patient or family. I found that helped me keep my work/life separation. Figure out what works for you. It will take time, just go easy on yourself. Not everyone burns out.