It's funny how polarising some words can be. Positivity is a beauty, it's right up there with journey when it comes to trigger points.
As you say @sister, you have several interpretations and there will be dozens of others. I think it's a crappy made-uppy word that isn't a verb or a noun; its a symbol of the Woo phenomenon and I blame social media. So there. Sometimes if there is not an existing definition for a perceived situation someone invents one. Wellness:/
Poets used to try to describe the fleeting feeling of well being and happiness that could be generated by observing a perfect flower dancing in a gentle breeze. There was a general understanding that a feeling of satisfaction was good. Now there seems to be an expectation it can be ordered as required. No flower or breeze? Here, have a meme instead. All better now? You should be. Don't be ungrateful.
Does feeling better make you better? Maybe. It's probably preferable to being miserable, if only because it makes life easier for those who have to deal with you. MXX