OP, you have hit the nail on the head and I have no doubts that you will come out from all this even wiser and stronger than you already are, and I commend you for that.

For what it's worth, I have a different perspective- coming from a girl, but I can relate to a lot of what you've written about your bf. There were a couple low periods in my life which I guess in hindsight were "depressive" periods, but during each one of those periods I pushed away my partners because I felt overwhelmed, unworthy, and almost burdened by their wholeness. I didn't feel like I could give them what they needed to be all there for them emotionally because I was struggling with my own internal demons, and I didn't want to drag them down with me. So, strangely, the "better" they were in terms of being supportive, whole, healthy, and intelligent, the more I shut them down and pushed them away. But I was still lonely and empty and oftentimes I would seek out people who were as messed up or worse off than myself; in retrospect, I chose them because they distracted me and I could divert all the "hard work" necessary for a healthy relationship away from myself and onto them to fix their problems. It was just my way of avoiding my responsibility to hard look at myself and work on what I needed to do to be the best partner I could be for someone. I should've used that energy to repair the emptiness within myself, but I wasn't self-aware enough to understand the dynamics at play. The "messed up" selfish partners never lingered in my mind once the relationship was over, though. The people I thought about, and still do, were the truly healthy and supportive partners that tried so hard to reach me during my low points; they stayed on my mind throughout the years. Even now I often think I would have been happy with them, had I been at a place where I could reciprocate that unselfishness and generosity and respect.

The best thing you can do is what you did. No pressure, but openness and honesty about your support. It's on him to realize and go through the long and hard process of becoming self-aware and growing into a healthier and stronger person before bringing someone else into the picture. Like you said, you must choose to be with someone you love who can give you a true partnership; someone you can rely on, someone who makes you feel cherished and loved and appreciated for all the love and brightness you bring to the table. Life is too short not to cherish each moment with our loved ones to the fullest. All the beautiful love you have to give in your heart is a treasure and a gift that must be given to one who will protect and guard it and recognize its precious worth; with all this self-awareness you have OP, you will find that person. Best of luck.