My wife and I have a rule - minimal phone use around one another. We hold each other to it, unless both of us agree to look something up. Perhaps it's because we both think it's rude, I don't know..
Now, although that works generally - my wife will often spend hours pouring over Instagram a week. She too, has mixed feelings about it and on the one hand wants to delete it, and on the other feels she needs it to connect to people. When discussing this with her (she wanted to talk about the struggle she was having), she realized everyone she was worried about leaving behind on Instagram were people we knew from high school - a decade ago.
As soon as she realized that, she deleted it. I think the fact that phones connected us across time and places, make it difficult to recognize we don't need it in many cases. The addiction comes from wanting to be included, but in reality - we're just segregating ourselves; behind the facade of happy photos. The truth we all know is that everyone on Instagram works for those shots, those happy moments, to share with... well, their collective of "friends". Many of whom they will never see again in their lifetimes.
For me, I only install functional apps on my phone, never user it for fun, and already have blocked all news sites outside of HN, Reddit, and a few other niche forums. I can access my investments, bank account(s), flash cards, w.e. - that I don't find addictive. If my phone died, I'd be frustrated (how do we decide who's picking up the kids), but I wouldn't go through withdrawal (I often leave it at home by accident).
Perhaps a healthy approach to the phone is looking at it as a tool, not as a way to be friends. Honestly, it's the social networking aspect of it, that's the issue for people. Life is meant to be fluid and limited - spend time where it counts, building deep relationships.