I think if the writers were consistent then House wouldn't be afraid of same sex relationships or being gay but we have him insisting in "Broken" I think twice that he's 'not gay' and then later on in season 7 as well he said it at least once. That's what I was referring to. I agree that House is likely concerned about Wilson's fidelity, but I don't see that actually being emphasized in canon (though House has shown his disapproval of Wilson's cheating ways). Plus House is the one having sex with all those prostitutes, all of whom were women. It's almost overkill, and I don't think the soul reason was that he was trying to hurt Cuddy, although that was definitely a big part of it). I could be wrong, but I just get this feeling from House's words and behaviours (inconsistent as they may be, especially from the first three seasons) that he would be much more difficult to convince that he had feelings for Wilson that went beyond the platonic. House has also made derogatory jokes about homosexuality and bisexuality several times throughout the series, but Wilson hasn't, not even when alone with House and not trying to be politically correct. One might argue that Wilson freaked out when Nora believed he and House were lovers because he's straight or deep in denial, but I say that might have been due to the fact that she hit a little too close to comfort (which he is aware of, not in denial of) and he was worried that he was being too obvious about his alternate proclivities which House might then pick up on and be alienated or repulsed by (because House has always pushed this macho image of himself and teased Wilson about acting gay). He did go to House after and tell him that she thought they were gay and asked House what they should do about it. If Wilson was the one in denial, I think he would have known what to do immediately because he would have been secure in his heterosexuality. I think he was feeling things out with House, almost as if he was judging not only House's sexuality by his response but also House's evaluation of Wilson's sexual preferences. Maybe I'm reading too much into it, though.

In a less than efficient way I'm trying to say that Wilson is more aware of his tendency towards bisexuality or homosexuality than House is but he runs from it or at least tries to hide the truth from House because House has been very loud about his macho heterosexuality and has made fun of Wilson in derogatory ways for acting 'gay' or feminine. Wilson might therefore believe that House would be disgusted if he found out that Wilson wasn't straight as an arrow and end their friendship. Therefore, Wilson runs away when he gets too close to revealing to House his love and desire for House, which Wilson is aware of, not in denial of (examples of running away would be when he was living with House after Julie (ran to Grace) and then when he gave House the organ in season 6 (ran to Sam) ); because he doesn't want House to be disgusted and terminate their friendship. Wilson's lack of dating since Sam left may be to the fact that the failure with Sam convinced Wilson that he couldn't hide the fact that he was gay or bi any longer (and unable to make a relationship with a woman work) but if he tried a relationship with a man and House found out House might be alienated, so he's chosen not to date at all. (Wilson 'knows', after all, that he couldn't approach House with his love for him because that would definitely push House away so, if he were to try a relationship with a man it would have to be someone other than House.)

Am I making any sense at all?

ETA some emphasis or clarify a thought.