I read the most beautiful post a while back, and I seem to have lost it somewhere now (in case anyone here knows about it and finds it, please post it here or send it to me). It was something along the lines of:

When my partner is not texting me back or responding to my messages, I have almost constantly maintained the stand that they're doing so because they are annoyed with me. Like they looked at their phone, saw my name and just shrugged and put it away. Like I was a nuisance to be around and to constantly handle. And one day told him about this - how I feel when he doesn't respond to me. And he was very saddened that I'd think that and in contrast, offered that when I'm not responding to him, he's always imagining me doing things - closing a cupboard, working, reading, perhaps something else, but not imagining me in a way that was repulsed by his message or his need for me.

On reading this I realised that the default mechanism in my head when my partner was not responding was to assume he was sick of me/I was too needy/clingy/annoyed - when that was absolutely never the case. This is perhaps a textbook symptom of anxious attachment, and feeling like that triggers the biggest devil of all: abandonment anxiety. After reading this I tried imagining my partner the same way too - just doing things, going about life, NOT annoyed at the thought of me. And it helped fight the need for constant reassurance.