Is it time for me to end my relationship with my boyfriend?

I'm a 21-year-old woman, and I've been dating my boyfriend, also 21, for nearly a year. Until recently, we hadn't said "I love you" to each other. I started getting a sense that something was off. Early in our relationship, he shared that he had a toxic on-and-off relationship with another girl, which lasted three months on, six months off, then back on for another three. He claimed he loved her but ended it, and she never forgave him. He’s been in one other serious relationship that I know of, where he really liked the girl, but she broke things off because he wasn’t expressing his feelings enough. The other night, I told him I loved him, but he didn’t say it back. Deep down, I expected that response, even though I hoped he would say it back. He opened up more about his past relationships and mentioned he hasn't said "I love you" yet because he wants to be sure. Now that I see all of this written down, I can’t help but feel a little pathetic. He's my first boyfriend, so I don't have anything else to compare this experience to. I'm feeling lost because I love him and want to make things work, but I’m not sure what to do. I've been loyal and supportive, but I'm starting to wonder how much more I can do. Aside from this, our relationship is actually pretty great. We have fun together, can be ourselves, and enjoy our time together. I just can't shake the feeling that he might be hiding something from me. I’m torn because I know he struggles emotionally, and I feel like I’m just hanging on. Is it worth having another conversation about this? He still follows that second girl on almost all platforms. I feel so confused and a bit foolish about everything.