Is it possible for one to be in love with the feeling of being in love, instead
Both Jyl and Alex have covered the territory, and I have little to add. It seems to be true that loving a person (or even an animal) and loving an object or thing (chocolate, or a feeling) are different. In the philosophy of love the question arises: if both these two phenomena are in fact types of love, what do they have in common in virtue of which they are love? A tough one. Alternatively, we could say that "love" for a thing is not love at all, but something else; it has some things but not much of anything else in common with love for a person. Still again, we could resort to a "family resemblance" account of love, in which case there may not be any interesting common feature that links all loves together, and we can meaningfully speak both of loving a person and loving a thing or a feeling. We do so all the time in English, at least ("I just love your shoes!"), so Ordinary Language is on the side of both these phenomena being genuine cases of love. Or, because other languages are more linguistically sophisticated, what OL-English implies is that Americans (and the British? who else?) have a screw loose about love.
Wasn't it Aristotle who claimed that we could not love (philia) wine, or be its real friend, both because the wine cannot reciprocate and because we cannot wish the wine well for its own sake (but only for ours). I once made this point in an essay on the geneticist Barbara McClintock. Others had said about her that she was friends with her maize plants and that was a big reason for her success in studying and learning from them. In that essay I worried that such claims made a Nobel laureate look like an idiot. Nowadays I would make the point a more subtle way.
Something else we might want to look into is what is called "the elenchus of Agathon," in Plato's Symposium, in which Socrates grills Agathon and in the process proves to him that his claim that love is beautiful must be false. Socrates also shows, en passant, that one cannot love love. I reconstructed the argument in an essay in Apeiron (years ago) and Martha Nussbaum offered her own reconstruction in an essay she wrote on the role of Alcibiades in the Symposium.