Lyric discussion by mattdan79 

To me this is a song about someone who has fallen in love with someone who probably just was having a casual fling.

It seems supported by the lyrics. Sounds like the "many too many have stood where I stand" is written about a guy who fell for a "heartbreaker" who has already moved on to someone else (hence "many more will stand here too").

Also seems like the protagonist had his ego propt up by his false notion that this person was going to stick with them (hence the "built me up then knocked me down again).

The lesson hopefully learned here is to not put stock in someone too soon, no matter how great they seem.

My Interpretation
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