[Skans]

I would go inside if it started to rain heavily, if large hailstones started to come down, if the police were engaged in a stand-off up the street, or to get a drink of water. I wouldn't consider it "retreating." Nor would I see any reason to "stand my ground," should going inside be the best way to avoid an interaction with someone with an apparent behavioral disorder who just may be infected with something incurable.

However, since you have brought up the subject of retreat, where I live I do have a duty to retreat if i am threatened, if it is possible to do so safely, unless I am in my domicile or automobile. It's not in the statute but the duty exists.

If that duty did not exist, and if retreat were safely possible, I would nonetheless retreat if I were endangered by an assailant. It's safer legally, it's better tactically, it's probably a whole lot cheaper, and doing otherwise proves nothing for me.

The bottom line is that, if I am in my own front yard (I understand that this may not have been the OP's scenario - not sure) and some drunk, nutty scary guy comes stagering down the street, whether I'm armed or not, I'm not going to tuck tail and run inside my house. Even if it's a relative's front yard, I'm not going to tuck tail and run inside the house. It's just not in my nature to act like that.