i do all of the above.
in general, i think objects of affection would be shocked at how much i would think about them apart from time spent with them. the differential between outer expressed behavior and inner wanting and experience is indescribably large.
action is undermined by a sizable fear aspect for sure, a kind of de facto sense of powerlessness unless feeling really balanced and being in flow (which for me usually requires purpose, social connectedness, depth mining conversations, etc), and real ineptness and lack of attention to the details of particular types of interaction that make the risk/reward split more ridiculously challenging because putting yourself on the line when you could be shockingly awkward and don't really know your way around in these kinds of situations as well as you'd like can be extremely discomfiting to the other person and extremely humiliating to you and just feel like a fucking trainwreck (that i feel like, as a w4, i'll horrifyingly want to watch in slow motion replay again and again and again... tho i'm doing better at this).
to be fair, this sentimentalizing does have to do with current mood state too (well, it probably does for everybody regardless of type). so it gets conflated with aspects of wanting like lack of intimacy, desire for self-acceptance, sexual frustration, etc. but it's also just because great connections with others are the most fun and fulfilling part of life and are easily and deeply missed with those who spark my own sense of possibilities. and seeing and being truly seen just makes me feel whole again, it draws me out and makes me feel connected to a much more lively sense of myself that was starting to disappear.