A lot of ponies complain about shipping, especially when it is with the mane 6 or any significant background characters.
Shipping in the sense of relationship and/or sex is a very dividing subject among the brony community; some like it, some despise it, some just don’t care, but one opinion seems to persist: you don’t ship with the mane six.
The most common argument made is disrupting canon or assigning sexuality to the sexually ambigious ponies, but isn’t that like, almost ALL fanfics written or drawn? Unless it’s in the show specifically or in the official backstory of any of the characters, it’s not canonical; thats absolutely fine though, because so many interesting things can be done with the characters. (another argument is the arrogance linked with shipping with any of the mane six, that’s just your personal spite though, which is best left buried before fights occour)
Take for example tumblr and its countless pony blog accounts. Unless crossed over, every single one of these blogs is its own separate universe. Characters do different things at different times, they may know different ponies, have relationships, different or deepened personality traits etc.
In canon or in any other fanon, Fluttershy haven’t even heard of Cobalt Snow, same goes for other blogs; There are no molesting princesses, or a sadistic and mutilated rarity, or a kinky pinkie pie, or..well you get my point, they’re all kind of existing in parallel universes (with some few crossovers of course)
Point is, it doesn’t matter; not to your fanon, nor to the show canon. Let ponies write their own concepts, let them ship with half of equestria, and ignore them if you don’t like it.
That’s all, sorry for incoherent rambling on my part, it just irks me a little when other ponies get so upset because somepony decided to draw their OC with a significant show pony.