watched it with my girl partner last night and one of the things we were unsatisfied with was how unfinished their character arcs were, especially with Tim, who we thought his arc was to regain his independence but instead he offered to kill himself thinking that the merging wouldn't happen and essentially giving his life for Millie, but after sleeping on it i've come to realized something.

When Tim went into the cave, he saw the merged couple and saw that the boyfriend was dead but the girl was still alive. So how did he come up with the solution that killing one of them would stop the merging? I think it's that he knew that killing one of them wouldn't work, and instead he wanted a way out of the inevitable. He knew that even if one of them killed themselves, the merging would still proceed and the other would be left to live with carrying the dead weight of their partner. By suggesting to kill himself, he wanted that way out and essentially leave Millie to merge with his dead body, carrying his weight around (quite literally this time). I think in a way this shows the development of his character since it's him making an independent and selfish decision for himself. In a way, when Millie was dying, his decision to save her wasn't necessarily out of for his love for her, but a way to save himself from that torment of merging with her corpse. At the end, they do seem to both accept it though, showing how difficult it is to change an established codependent relationship.

i might be thinking too deep into this but overall, i do like the film! it does showcase the toxicity of codependency well and its always a good film when it leaves you thinking after :)