I'll add something that will make it easier to tell. For now, you can tell how much Ori likes you by the interaction intro text (e.g. Ori is looking at you, Ori likes being with you, Ori loves you passionately).
Actually, forgot to mention, if you press F3, it gives you a debug text box with the relationship value (RV). This gives you the exact value of how much Ori likes you. But again, I'll add something in the next major update.