Nice game! The puzzles were HARD. Like really, the difficulty curve is really steep, probably a bit too steep for a jam game x).
The "not alone" mechanic is introduced very late in the game, when I feel it should have been the core of the game, that's too bad :/.
Overall, I feel like you are very talented at creating difficult, but rewarding, puzzles, but you also need to calm down and create simpler puzzles to let the player experiment with the mechanics ^^.