wow this was incredible, one of my favorites so far. i never had to think about navigating a puzzle like this before. i went through multiple stages of false assumptions that i later reevaluated. i got all 3 endings :)
once i figured out the rules, i quickly deduced a route and was about to comment on how the full heart solution was too easy because there is really only one option for most of the path, but that single heart in the corner made the whole puzzle something special. it got me stuck long enough that i actually stopped and did the other ending first before i figured out how to manipulate things in a way that would let me solve the full heart solution. really good!!