Love is "just chemicals" in the same way that anger is "just chemicals". The chemicals are the substrate, but to say that is not very informative. Analogously you also wouldn't say computer software is "just electrons". Beware of "nothing buttery"; reduction is a great thing, but only if we truly understand the reduction (as in, heat is movement of molecules).
Re: determinism, I expect the whole process to be non-deterministic through and through, such that say what you had for breakfast might as well have some amount of influence on your social interactions.
Indeed. Chemicals are the implementation. That doesn't mean they are the essence.
In fact, I think the design of a thing is closer to its essence than the implementation. Moonlight Sonata is neither just bits, nor just vinyl, nor just vibrating strings. In any implementation, it is Moonlight Sonata. The essence of it is the music, the information, Beethoven's intent and insight.
Love is the same way. Of course consciousness and will are implemented in chemicals. They have to be implemented in something. That does not make them less real.
I think you have a fair point. I might have become a bit too overzealous in my argument via reduction. But yes, anger is definitely "just chemicals" in the sense that some people get angry quicker than others.
Again, although I'm forced to concede your second paragraph that there might be some influence by what you've eaten yesterday, I'd like to believe that they're not that large. Because, if that were true everyone who'd eat (for instance) spicy things would constantly be in a state of irritation and anger.
People's temperament, moods, general thoughts might as well be a pre-seeded RNG.
Re: determinism, I expect the whole process to be non-deterministic through and through, such that say what you had for breakfast might as well have some amount of influence on your social interactions.