element, sorry for butting into this discussion so late. I am not sure how helpful at all I am going to be, but - are you taking any medication? I am sure you have been asked this before. However, this is not the first time you post here about your problems and I do not recall you saying anything about medication before.
I have not experienced depression myself, but my DH has long-term diagnosed depression and anxiety issues and what you write about yourself fits with his behaviour and his conception of himself. From what I know from years of interaction with my DH, depression/anxiety is a strange combination of rock-bottom self-esteem and a rather narcissistic self-centred view of the world. You say that you feel worthless and yet you demand recognition and approval from the world. My DH, for instance, had a near constant need for approval, everything revolved around him. He would ask me multiple times a day whether something he said or did was ok or not. He could not just do or say something. It had to receive official external stamp of approval. I find your need for external approval very similar.
My DH also constantly monitored the behaviour of others for sings of whether they approved of him or not. Every little gesture was analysed - how somebody looked at him, whether they said hello or not. Anything anybody did was always interpreted as relating to himself. For instance, a co-worker was not allowed to blank my DH just because he had a bad day at home. My DH always interpreted the blanking as the co-worker having a problem with him. It is almost as if the world and other people within it are not allowed an existence that is independent from DH. Again, this is something that is very prominent in your posts. You do not allow other people to have feelings and thoughts of their own. You speak about others only in the relation to yourself, as if you are the centre of their world.
The truth of the matter, as multiple people told you already, is that there is no external reference point against which we can measure our worth. Seeking it is a futile quest that will only lead to using other people as a means for feeling better. And whatever other people say to you, it will never ever be enough because there will always be other people who have not yet provided their approval or other situations where approval has not yet been given. Seeking your own worth in the approval given by others is an endless and futile undertaking. No matter how much others praise you, you will always feel that you are lacking.
The only way out is to find the reference point within yourself. Yes, it is not "objective". Yes, there is no way of knowing whether you are "correct" in your evaluation of yourself or not. But this is normal. There is no one objective truth out there about anyone, no one objective measure of the good. We are all alone in our own truths. And it's OK to be so. The path to internal peace does not lie though approval by others but in the acceptance that every single human being, including yourself, has a precious private world inside, a world that is valuable without the need to be "true" or "correct". It's really like that spoon quote from the Matrix: "There is no spoon. It is not the spoon that bends, but only yourself."
I feel that depression and anxiety at least partly derive from existential angst. People grapple with their own mortality, with the point of their existence, all of which are seriously scary subjects. But - it's OK not to have a point to your existence. Just existing, without any point, is wonderful in itself. You do not need for somebody to come and give meaning to it. There is no measure of good out there, just a load of stars and planets and galaxies that do not give a shit about what is good and what is bad but look rather nice nonetheless.