I [18M] feel like I might not have feelings for her [17F] anymore.

We have been in a relationship for over a year, but lately, things have started to feel off. We've had quite a few arguments in the past couple of months, and while things seem to be calmed down now, I've come to realize that my feelings have changed. There was a time when I couldn't imagine my life without her, but now, I struggle to envision a future together, and I feel terrible about it, especially since she still expresses her love for me. I find it difficult to just walk away, especially since I lost those feelings a few weeks ago. I've been trying to reignite the spark and see her with the same affection I once had, but it hasn't been easy. I've thought about ending the relationship, but I feel guilty for a couple of reasons: firstly, she is still very much in love with me, and secondly, I was the one who took her virginity. That makes it feel like I can't just leave without considering the impact it's going to have on her. I don't want to leave if there's a chance to revive the love I once felt, but right now, it just doesn’t feel the same. I’m genuinely unsure of what to do next. I could stay in hopes of rekindling those feelings, but if I don’t, I’d just be stringing her along. However, if I decide to leave, I know it would hurt her deeply. What should I do moving forward?