Until a few years ago, I would only have counted two: "Every Rose Has Its Thorn" by Poison, and "Tiny Dancer" by Elton John.

The former is probably largely because it might have been the first song like it that I'd ever heard so it really stood out from the crowd. (I was also roughly the age at which most people's lifelong "favorite kind" of music is set so they always remember whatever was out at that time the most fondly.)

The latter is simply because of the poetry, what the words say. Wikipedia's article about it claims that it's hard to undertsand, but I can't figure out how it could be. It's pretty simple & straightforward. The man who wrote it and the woman he wrote it about (and later married... but then divorced a few years later) met while working for Elton John's tour together, and it's about sitting back together in a seat on a bus after a long day of exhausting work, watching lights go by in the dark and thinking back on their experiences together putting on show after show. What makes it special is just the fact that it's specific to the people involved in it. Most "love songs" just recite the same old generic interchangible could-be-anybody catchphrases like a political speech, but this one has personal details that let you get to know these two individuals a bit, the kind of individualized stuff you'd include if you were really writing about a specific person yourself, because real feelings are often about little insignificant-sounding details.

In the last few years, though, I'd have to add several more to the top-tier list with those two. For the ones with lyrics, it's generally for similar reasons to "Tiny Dancer"; the words have a message which sounds like what someone who was actually in love might say, instead of just parroting back standard empty love-song gibberish we've all heard a thousand times. But sometimes the words have some help from the other aspects of the music, too...

"Sleep" by Melissa Etheridge
"Stay Now" by Jem (Jemma Griffiths)
"Flying High" by Jem
"Scared Of You" by Nelly Furtado
"Try" by Nelly Furtado
"Picture Perfect" by Nelly Furtado*
"Build You Up" by Nelly Furtado
"Childhood Dreams" by Nelly Furtado*

*These two stand out because they're a bit indirect, framing the "love" theme in terms of other feelings and aspirations in a metaphorical style that would be at home in un-sung poetry. "Childhood Dreams" dosen't even really tell you where it's going until the very last line, sorto like Metallica's "Sad But True".

If it seems weird for so many of those to be from Nelly Furtado, it's because they're by Original (First Two Albums) Nelly Furtado, a completely different person from the Nelly Furtado that everybody knows now. The one you've probably been hearing on the radio so much lately and seen getting one or more of those little trophy things is Third Album Nelly Furtado... known to fans of her first two albums as Sellout Nelly Furtado because she's so unlike the original, so blandly conventional and lacking in what had made Original Nelly Furtado's two albums so special, and of course so much more "successful"...

Anyway, here are several that have no lyrics (as a lot of my music collection doesn't) but still seem to say the same thing to me with instruments alone... although I must note that in several cases, I don't know what the creators intended and my interpretation might not be what they wanted!... (They are without doubt "relaxing" music, and maybe my idea of love is tied to relaxation, but sometimes relaxing music is just meant to be just that all by itself... or even about something else in particular, like death!)

"Fire Walk With Me" (theme from "Twin Peaks") by Angelo Badalamenti
"My Wife" by Mark Isham
"Watermark" by Enya
"Gymnopédie" by Erik Satie
"The Swan" by Camile Saint-Saëns
"Pavane" by Gabriel Fauré
"Our Winter Love" by Bill Pursell
the love theme from Dances with Wolves by John Barry