So- first off. Alex is not and never was representative of Andrew Allanson. Alex is a worst case scenario depiction of the kind of person who would unhealthily obsess over this sort of missing persons case.

That also wasn't Sammy at the end, she very notably had the same outfit as the Blue Woman who showed up outside the factory hotel. Alex getting his details mixed up. They're not soulmates, Alex never even met Sammy. The entire story is told BY Alex, and you see what he wants you to see. If you realize that, you'll start to notice lots of little inconsistencies and can piece together what's really going on.

Alex isn't an important person in any regard, and nothing about him is meant to be seen as good. He doesn't even ACTUALLY confront his issues when you get to the Alex comet, he does it in the most placid way possible to make it seem like he's improving when he's not.

I think you made the mistake of trusting what Alex shows to you :V