Ah well, at least you know happiness is in you somewhere. Shame that it was short-lived due to this ex.
I hear you over feeling 'whole' with someone - but sometimes you can feel that way just about yourself. You felt it for a few fleeting moments. something put the wind in your wings and it was not a women, and you never mentioned taking meth amphetamine also which means you felt some genuine happiness.
Losing someone can be like losing a limb. I know people who lost their loved ones after 40 years or more of being together. In fact, you'd happily have all your limbs taken off just to keep your soul mate.
What you feel is love - but I doubt she is the one. If she was, you'd have likely been reciting poetry to her or sending flowers around (or borrowing some from a park)
IF there is any doubt in your mind and you've not communicated with her - just make sure its over. If you've already exhausted yourself trying to win her back then forget it.
After all, if a women ignores you at a bus stop or anywhere - that could mean anything. Given your the man - in my book I'd expect you to have said something, even if it was just a pleasant, hello how its going. You could always apologise for not acknowledging her - that would do no harm. Maybe you feel a bit guilty about not doing so. It's bad manners unless she is some kind of evil hearted women who would maybe claw your eyes out for doing so.
Good luck - congratulations on feeling OK in yourself and at ease with the world. Capitalise on that - bear in mind you'll feel it again.