OK, first of all. There is no canon ending. There will be no canon ending until a future SH installment produces one. And a lot of us got "Leave", more I think than got "In Water". It primarily depended on how generous or stingy were were with our health drinks. The ending you get, or the ending you favor, determines what's canon.

Second, the Leave ending is not sweet. It is ambiguous and open to all manner of interpretation. All wew know is that Laura and James both leave Silent Hill alive and at more or less the same time. See "Laura's fate post-game" for more on that.

Third, none of the three "first-game" endings are dominant per se. They are actually very Freudian in nature. according to Sigmund, the human psyche is divided into three elements: the id, the ego, and the superego. If James allows his id (emotions and desires) to dominate him, he embraces his delusion. If he allows his superego (rules, logic, and conscience) to dominate him, he destroys himself. If he allows his ego (the person that he is) to retain power, he accepts reality and escapes with life and sanity intact. Since the ego takes the energies of id and superego and relates them with the outside wordd, it could be argued that "Rebirth" is where the outside world of Silent Hill dominates: it produces the four elements of the ceremony and compels James to attempt to carry them out.

Fourth, the endings appear to balance themselves out, in a dark Silent Hillish kind of way. In "Maria", James forfeits his sanity. In "In Water", he forfeits his life. In "Rebirth", it could be interpreted that in reviving the cult, he forfeits his soul. In "Leave", he finds sanity, life, and a possibly faint hope of redemption. So with one good ending against three missteps, that would imply that "Leave" is the canon ending.

And fifth, I reiterate. To die is to lose. Deal with it.

Leave could be the canon ending. It seems to me that in each of the games, you can't really go home again once you leave Silent Hill, no matter the outcome of your adventure. Your life will never be the same, so whether you move to avoid the cult, you murdered your wife, some dude tried to turn your apartment into his mother, aliens abduct you, etc., there really is no normalcy again and home might not hold the same comforts for you anymore.
There are a thousand reasons to explain why James never went home besides him offing himself. Can't risk Laura accidentally blabbing his secret, can't risk Maria looking and acting like Mary's slutty twin, can't risk all the attention Mary would get if she suddenly came home perfectly healthy or trying to feast on brains.

Of course it doesn't "make it all better". I mean, if it did, Leave would be impossible because James could just waltz back to his old life, like it all never happened. He can't. If/when Mary's body is found, an autopsy will verify that someone killed her. James will be investigated, and he'll get thrown in a 6x8 metal box with a sagguing mattresas and a stainless steel toilet that leaks. If James leaves Silent Hill, he has to cover up all connestions, sever all ties, adopt a new identity. James Sunderland dies, and a new man takes his place.

You do have a point there oddish.

The bodies do represent James Aura it has been stated he came to silent hill to die and a manafestation of that wish is all the bodys of himself around.

Mary forgiving him dosen't mean he still didn't do it and he knows that.

And he has to deal with it. SH2 is a richly symbolic game, and just because something isn't stated doesn't mean it's not meaningful.

at the end of SH0, the Good ending anyway, the endless mists of Silent Hill vanish. The trial is finished, the nightmare is over. Even in the most upbeat of SH2's endings, James remains swathed in mist, a metaphor of sorts for his uncertain future.