I have been coding for almost a decade and I don't think I have come home any day and felt like, "oh, today I will code this!". Nope. I always leave work at work - coding, studying, learning about work. It's not really a discipline, or an attempt to keep work and life separate. I just don't feel like it.
After work it's just reading, films, walks, sports etc for me. I used to get bothered by it seeing other people code and learn tricks, tools, and paradigms at home. Thinking whether I am in the wrong profession, or I am doing it wrong. But now I have accepted it as this is who I am.