Well, just to add my experiences of a Sun square Sun apsect. It is a very tricky aspect indeed.I am currently sharing an apartment with someone whose sun squares mine exactly and I tell you that the way we relate is suprising.
The guy is a Virgo and I am Sagittarius.
-Firstly we are both mutables and this is the point of reference.
The mutability, as far as he is concerned, is his ability to be flexible and conversational.
Our lives are pretty separate but he always has a story to tell that is both weird and fascinating all at once.
I've noticed that if we should have an argument/ disagreement where he/I explode, there is often residue "tension" between us until the dispute has been resolved.
Usualy I'll laugh anout how ridiculous I acted or he'll say something like " I didn't mean it, don't take it personally."
He claims not to be a grudge-bearing individual and not sensitive, but I disagree. If something is bothering him, he wont be able to strike up a peppy " Good mornin dude, do you know what I got up to yesterday?" in the morning.
At times he does irritate me and claims that I am moody(couldn't agree more) and so when he wants to say something to me he often starts with something like"Okay, I know that I am irritating you with this but I don't care. I want to say that......"
Its not bad living with him at times as he is not a pushy,demanding individual(I think that has to do with his mutable quality).
So when the dishes are not done, I don't fret and call an inquistion and neither does he; whomever wants to wash the dishes can and they'll be no silent treatment by the other individual who feels that they are cleaning up after the other.
The worst though is when I get emotional and passionate about something and he takes a very cold/logical view:
Me: "Why did you play the music so loud at 2:00 in the morning?"
Him: "Well, I didn't know that I was playing the music that loud because from my room I didn't think it was that loud.Why didn't you say anything to me(shifting the blame)".
Me: "Dude, I shouldn't have to get up and tell you that playing music at 2:00 am in the middle of the week is unreasonable. Who does that anyway?"(fuming!!)
Him:" No, don't blame me for your mood. You chose not to sleep. You could have gotten up and told me that the music is too loud and I would have gladly reduced the volume..."
Me: "Ok(calming down), fine; I should have made an effort to let you know how I feel instaed of brooding until 6:00am but you should take the responsibility and stop shifting the blame to me if you were wrong.
Him: "I didn't say that I am not taking any blame for you not being able to sleep but hey, maybe next time you'll know better then to just sulk all alone and then snap at me in the morning.
Me: "There wont be a "next time". Do you understand me? Not ever!"
And so the conversation goes....at times I get irritated with him for no particular reason. That could also be because we are living together...I don't know.
Our moon signs are also square:
Mine: Cancer.
His: Aries.