Discussion about the plot and ending (SPOILER)

[DOOOODGE]

Soooo, I've bought this game during the last halloween sale and I've just finished it and I think it doesn't really deserve hate.

Played it with mouse and keyboard (I don't have a VR and don't plan on buying one), and I'm really confused about the ending.
From how I see it, Raymond was a computer scientist obsessed about fully transfering a person's conscience in a virtual world so that one "self" can live past his/her physical body. He felt he was on the verge of a breakthrough...
But he was so focused in his research that he didn't see how his life was breaking apart. His wife was depressed and under meds, their son went from a joyous and brilliant child wanting to walk on his father's footstep to a frustrated kid who spent his time cursing and hating his dad.
Then... What? I've read here and there that the general opinion is that he killed his family and then himself, but I tought he did just kill the dog The fact that the whole family is in the simulation, though, means that they're supposedly all dead, or at least their consciences have all been 'transfered' into the virtual reality.
The last two video logs, though, show a Raymond collected and calm, as if that dark moment of his life was ended. So I don't really understand what happened.
From bits of information here and there by interacting with objects, I take that there was some sort of "conflict" in the VR because everyone had a different view of their family life and thus, several, conflicting versions of their home were overlapping, causing glitches.
The crystals were the key in the sense that the simulation's frequency had to be realigned with each family member's own frequency.

But then what was the 4th crystal? And who was the virtual "monster" attacking you? And, more importantly, who are "you"? Raymond's conscience? Each family member's conscience trying to fix stuff? From some video logs, for a while I thought the PoV character was grown-up Benjamin trying to fix his father's work, but it seems Ben died as a kid. It could be a guy from one of those companies that rejected him, who found Raymond's bequest.
I don't really understand the ending.