Healthy or not... Kristian, you really need to sit down and talk with your young friend. I sense that you are allowing him to slide and skirt the boundaries that you set, because you enjoy spending time with him, and want him to think you are a great friend.

That is all and good. Except, you are not his friend first. You are a mentor and a teacher to him. Just like parents cannot be friends first. You have to explain to him what you won't accept in his behavior, and if he doesn't respect your wishes, then you don't have a choice but to "punish" him.

In example, if after you've explained to him that he needs to respect your privacy, and he again walks in on you while you are dressing. Tell him that he is no longer allowed in your bedroom period. You give him priveledges by letting him into your home, so you can revoke them (permanently or temporary) for not following your set boundaries.

It sounds like he is testing you, to see how far he can get. Be loving, but be firm.