Hello ennui.: I'm so sorry to read of your struggle. I also have harbored a deep hatred of myself for many years. I know some of what has caused it. Yet the roots of it go back to before I have any memory. It is a ball of wire that will never be untangled. (By the way, more than once, I've been to that dark place you are thinking you might as well go to.)
I was struck by your statement regarding showing compassion for yourself, "like I am some baby." I would like to suggest to you that showing compassion for yourself is not babyish. It is one of the most difficult, most profound practices a person can undertake. And it is directly related to the act of showing compassion for others. The two are inseparable. I cannot show compassion for myself unless I can have it for others as well. But I also cannot have compassion for others without allowing it for myself.
Of course, the problem is that therapists throw statements like: have compassion for yourself... out without any real understanding of what they're talking about. It's just a "throw-away line". It absolves them of responsibility. They've told you what to do so, now, if you don't do it... it's your own fault... It degrades a profound act. It is possible to sit with thoughts & feelings of the deepest self-hatred, to accept them, to watch them as they come & go, to breathe into them with lovingkindness, & yet to hold your seat... to accept your demons with compassion. And just by coming to the realization that one can do this, one develops a new perspective with regard to one's self-worth. So I hope that you will take a second look at the concept of having compassion for yourself & consider that it might be the most difficult, the most challenging thing you might ever do... but also a thing of great strength & beauty... something of which you could rightfully be extremely proud. I send warm thoughts your way with the hope that it might be so...