"it takes something deeply fucked up to make an entire website celebrate a hallucinated wedding."
WTAF are they talking about? Because as far as Spn goes there was that time that Becky love potioned Sam into marrying her...
... and the show chose to frame this shot like this, putting Dean in the middle of a illusory heart and looking like he's gonna puke at the idea of his brother marrying someone else. (7x08)
Or the end of season 8 when Sam and Dean kinda, sorta, got inadvertently handfasted in that church...
With Crowley as their witness, they stood in a church and Dean declared his undying devotion to Sam, bound his hand, they chose each other over saving the world, and hugged. (8x23)
Sam and Dean were the ones always being compared with or mistaken for a married couple. Sam and Dean not only had several break-ups on the show, but Dean even said, "What did Sam say? Does he want a divorce?" And the best part of that was that he said it to Castiel, who then just reassured him that it would take "a lot more than trying to kill [Sam] with a hammer to make him want to walk away." (10x03)
And like, again, ship what you want to ship, but the only relationship that Dean had in Supernatural that was compared to being married to a guy was his relationship with Sam, his brother. And Castiel's feelings for him were one-sided, as clearly stated in the script for the episode where he confessed his feelings...
"Dean can't reciprocate, but Cass doesn't need him to."
And finally, the one who was shown to be widowed at the end of the series was Sam. There was an entire montage of him grieving the loss of his brother for the rest of his mortal life. And, he named his son Dean! Garth named his twins Sam and Cas, but Sam named his one and only child after his brother who there were six photos of around his deathbed. Six. No photos of the mother of his son. There were three of Mary, two of his son, one of John, one of Bobby, and SIX of him and his brother.
When Dean was dying, he said things like, "It was always you... and me." and "I love you so much, my baby brother." And then when he got to heaven he was met by Bobby, declared the place "almost perfect" because Sam wasn't there, and then went and drove around by himself (and apparently fucked with an AU for funzies) while he waited for Sam to catch up. (15x20)
And while I do not think that Dean and Cas had any sexual chemistry, Destiel is a popular ship so to each their own, I guess. But yeah, 'canon' means what actually happens on the show, not stuff folks just collectively make up.