Yes because she was from his future.
He couldn’t remember cause he hasn’t married her in his current incarnation. The marriage she is apart of what happens to the doctor many regenerations from now. As River mentioned in the library DT’s Doctor was still very young to her. Which means she will marry him in his distant future.
[SPOILER] She is meeting him out of order as she will say.
And darnit she handles the TARDIS better then he does. COUGH Parking BrakeCOUGH [/SPOILER]
As far as the Doctor being Asexual its more like trysexual. He will TRY just about any kind of sex. White, Black, Yellow, Green even. One head two three all the same.
Right - I know that’s what I was saying. He doesn’t remember being married to her because for him it hasn’t happened yet.
Though she sure knows how to push his buttons. Both the Tardis and his.
You forgot the IYKWIM!!! 
True, should have included it.
well i’d call it D-sexual we all know the dude is into Daleks and who can blame him after all hot!!!
River Song - I don’t think they ever explicitly say she was The Doctor’s wife, but in The Silence of the Library, they established at least a past intimate relationship between the two on the basis that she knew what his real name is (which, no one else ever did in the series, or am I forgetting someone?)
I also think the Doctor is omnisexual - whatever species, whatever gender (since the Doctor’s gender is sort of a ? - like, technically, he could regenerate into a woman?). I mean, he’s hundreds and hundreds of years old and the only one left of his species. I imagine that would make anyone very open and non specific when it comes to being attracted to someone.
I agree. And frankly, I really appreciate being able to watch at least one show that does not feature naked people getting it on. It certainly isn’t necessary to make Doctor Who a good show.
I know this was last commented on in 2010 which is 11 years ago now, but no one on here clearly even knows anything about asexuality. I don’t feel like explaining it right now, but I’ll add that I personally see the doctor as asexual and there actually isn’t anything substantial in cannon to contradict this. I also think they’re aromantic, and although there is evidence against this it’s still possible, as actions and attraction can be different, and they aren’t really shown to be actually attracted to anyone in a romantic/sexual way, that’s just one interpretation brought about partly due to amatonormativity, it could just as easily be platonic.