LP Gains Vs Losses

So I recently got demoted (tried to carry myself in off-roles because carrying from Support is either 500% harder, or you go full AP and don't actually support at all; this went badly). I sort of understand why when you're in Demotion Protection your LP Gains need to offset any LP Losses whilst you sit at 0LP (IMO Demotion Protection is just stupid, then again the separate hidden MMR and visible LP & Rank system is stupid too). However, now that I'm down in a lower Division, and not in Demotion Protection, WHY AM I LOSING 23LP BUT ONLY WINNING 14? What is the purpose of Demotion Protection if it COMPLETELY fucks you if you do demote?

Now this Split I'm gonna grind my way back up, but next Split, I'm probably just gonna stop playing if I hit 0LP. WHy risk the misery that's now ahead of me ever again?

LP changes and Ranked as a whole in general NEED to be looked at, but this may well be the thing that drives me away from the game in future (at least during Splits).