How can you just “fall out of love with someone?

I (19f) spent a year together with my first boyfriend(24m) who took my virginity. He dumped me a little less than two weeks ago. I’ve always been extremely big on communication. Everything in our relationship seemed perfectly fine. He would text me every couple hours saying how much he missed me and loved me. He told me how serious he was about me and that I was “perfect.” He told me how happy he was with me. He told me all of these things up until a few minutes before we broke up. We had sex like normal and hung out like normal. The only thing I noticed different was that he wasn’t seeming to share his feelings with me as much the couple weeks before this happened, and so I would tell him to please talk to me about anything on your mind. We had sex about an hour before we broke up. He looked into my eyes and said he loved me. After we finished, I talked to him about how I was recently feeling really depressed and lonely sometimes (due to the fact that I struggle with severe depression). He knew about my depression getting into a relationship with me and it’s something I’ve been working hard on changing. I’m mainly depressed because I’m still surrounded by toxic family and traumatic memories. I recently just got out of high school and have been saving up to move out. This is a normal conversation for us. I share my problems with him and he shares his with me. All of a sudden, he blew up and said he didn’t love me, I wasn’t enough for him anymore, that he wasn’t happy with me, and that he didn’t know if he wanted to break up or not. He said all of this while touching me and calling me babe. I just ran away. I don’t understand. He said he was feeling this for weeks, yet never communicated. It shouldn’t have gotten to this point. Relationships aren’t just about feelings. They are also about work and commitment. If you truly cared about your partner, you would talk to them the moment you started feeling distant and try to rekindle and reconnect. If that didn’t work, then fine. Dump me. How can you just have sex with me and lie to my face for weeks? I’m scared I’ll never be enough for anyone. I’m scared I’ll never be able to trust the words “I love you” from another man. I’m scared that I’m not special enough to be loved for the rest of my life by a man. My self-confidence is completely shattered. I feel hopeless and empty.