Rainbows in the Dark Lyrics

Lyric discussion by coughingcolors 

Cover art for Rainbows in the Dark lyrics by Tilly and the Wall

Can someone clarify this:

"Now they're drilling my teeth while I'm soiling sheets With my lover, she's counting the diamonds on rings And even when truth doesn't help with the sting"

I don't really understand it. I mean I know it's literal meaning, but I don't know what it means pertaining to the song.