Higurashi Ch. 1 Onikakushi Full Series Spoilers General

Does anyone here know what the opening was speaking about?

From the start, it seemed like someone talking about a lost love (I can’t remember exactly because I haven’t read this in a long time) or abandonment before what I assume to be committing suicide, I’m not really sure.

At first, I assumed this was Keiichi’s thoughts before clawing his own throat out, but the sounds are those of the bat being hit against an object, so it could also be the moments before he (I assume) murders Rena and Mion. Are either of these assumptions correct?