1 - Olivia Newton-John - "Hopelessly Devoted" (J. Farrer) - From the motion picture soundtrack Grease (PolyGram, 1978)

I guess mine is the not the first heart broken
My eyes are not the first to cry
I'm not the first to know
There's just no getting over you

I know I'm just a fool who's willing
To sit around and wait for you
But baby can't you see
There's nothing else for me to do
I'm hopelessly devoted to you

But now there's nowhere to hide
Since you pushed my love aside
I'm out of my head
Hopelessly devoted to you

My head is saying fool for a game
My heart is saying don't let go
Hold on to end, that's what I intend to do
I'm hopelessly devoted to you

2 - Torias and Nilani's love story is explored in Star Trek: Deep Space Nine - "Rejoined" (ep.478-1995).

3 - Space:1999 - "Collision Course" (ep.13-1974)