One thing I've done just now that seems to have helped, is going through a pretend goodbye scene in my head with her. Significantly helped it seems. Saying whatever I wanted to say to make amends, wish her well, etc. . I know it sounds kind of corny or wimpy (and obviously wouldn't do it in real life), but since I never had a goodbye or blowout with her (I just quietly removed my connections with her) - I think it was something that was missing all along. I think the mind can believe that it's real if you imagine or go through it well enough. I've read that for procrastinators, sometimes the act of imagining that you've done something, can remove your impetus to actually perform it. As perhaps you somehow believe subconsciously 'Oh, I've already done that, haven't I?'.
'I don't know that I want revenge, more just an acknowledgement that I wasn't disposed of without looking back.' - I agree with that sentiment, that's something I'd like to feel as well, rather than revenge per say. However, I don't think there's a direct way of me being able to find that out. The options available to me now are NC... or reaching out and most probably looking pathetic (regardless of approach). And ultimately, simple NC and moving on is objectively the best option.