Hello! Just registered. Glad to have found you!

I think it likely Sherlock manipulated Sally, like acting interested to get an opportunity to get something relevant to a case, before the Yard let him have full access. That " old friend" bit sticks with me. If he used her like he has Molly. He would have been even more desperate at the beginning of his career. I also agree he probably switched the relationship off by disclosing things very private (hence the projection of "freak")

I would up parasitic lifestyle as he requires John to do simple things for him such as bring him phone and pen.

Sally is definitely something. That degree of hostility is meaningful... and she is introduced as an "old friend". I think that means they likely have a past ( the "old" part), and were *once* friends .

Ok first of all, deep breath so I dont take this as a personal attack. I'm not very good at not taking " who told you and multiple question marks and questions without other commentary as not a personal attack, but I will try.
My definition of my sexuality comes from research on my part. A lifetime of it. No one told me what I was or wasn't. I think all labels are inadequate in some way.. people don't fit neat categories often. I also believe sexuality is fluid and moves along a continuum and can certainly change. Even catch you off guard. Is your issue with how I choose to self-define, or that someone else may have stuck this label onto me without my consent?
As far as lust goes, I said that people have it. Not everyone. I don't. But many do. Lust exists. Nothing wrong with that. 
I put "normal" in quotes for a reason. "Normal" is a loaded concept. There are things that are probably typical, or more or less common. I use the word in terms of " the norm", not to support some false normal vs abnormal dichotomy.

The many Watsons have always portrayed Sherlock as lazy and messy ( apart from the vanity of personal appearance).
I was thinking that anyone with that degree of observation would have a daily struggle detaching from his environment. I mean, can you imagine his cleaning a bathroom? It would never be done, never be clean enough. The details would jump out to him and the cleaner it got the more the details would just stand out. Better messy and chaotic so it can be ignored. A messy space is far more soothing than an almost clean one.

I agree that Mycroft is never wrong. He can be deceitful, but never mistaken.
I can see Sherlock having a lot of sexual experience, but no relationship experience. I can also see him having  neither. To me he is always about extremes.

Ancients Gate- I agree. I'm no real student of psychology either, but there was a criminally minded sociopath in my family and the guy was obscenely charming, not brusque. As far as true introverts, once you break through the wall I think you usually find an extremely sensitive person in desperate need of protection.

Basically: Someone who does not feel primary sexual attraction, but can react sexually (in response). Somewhere in between a traditional asexual and a fully sexual person. A Demisexual usually needs to be tuned into a relationship before they feel sexual connections. They wouldn't look at a random person and go "wow that person is hot, I want to sleep with him."

Yeah, I tend to defer to Mycroft as well, though being a virgin would be very impractical. Wondering if this could just be an " insult" he knows isn't true, or even a comment Sherlock could  use to his tactical advantage as "proof" he is s virgin when he really isn't; but when I think about it more, I suspect he actuslly is a virgin.
But still hope he is asexual/demisexual, not merely celibate or lacking "opportunity". I would think he could create "opportunity" if he wanted to. He could play people and become whatever they wanted to bed them. With his disconnect between heart and mind I don't think he would have trouble doing this if he truly felt a sexual need/urge that wasn't a distraction. I guess what I'm getting at here is if he is a virgin it is not out of fear of sex or out of nobility or chastity.