Yup, sure can.
Nothing needs to be decided immediately. "Falling out of love" can happen, even when alcohol isn't in the picture. I left my first husband after 15 years of good, solid sobriety. He was, and is, a great guy. We are still very dear friends. But I didn't feel in love anymore (assuming that I really know what that kind of love actually IS).
I don't think anyone "owes" a continued relationship with anyone. All you owe them is to be kind and fair and to avoid unnecessary hurt. I know my husband was VERY hurt when I left him, but I didn't stay for the sake of not hurting him at all. I felt if I HAD stayed, more hurt would come to him because I couldn't be the kind of partner he wanted (and, honestly, deserved). But in all ways throughout our split and after I was as kind and fair as I could be.
Give it some time. Your feelings will become clearer.