One short answer is work on your boundaries. I found this essay, complete with illustrations to be wonderful. At the end are some very good and fairly specific examples of where to draw healthy boundaries.
www.alturtle.com/archives/173Thank you for the article! I read the first portion and absolutely love the castle analogy.
Next thought: Decide for yourself what is your business and what isn't. Don't be afraid to make 'wrong' decisions this way. If you do, you will soon find difficulties arising from that and get to re-examine it. (Both the stressful reminder to re-examine and the chance to do so are free! Every Time!)
I like that. I do have to reign in my tendency to be a bit too nosy with my husband and his business though. I know that is a weakness of mine. With normal people, they have boundaries in place so it is a lot easier to gauge when I am being too nosy.
Sounding like a jerk by whose standards? Use your own.

I do use my own standards. I have set pretty high standards for myself when it comes to being "nice". If I wouldn't speak a certain way to a customer, why the heck would I speak that way to my spouse?
Your standards of what is being a jerk for you are YOUR BUSINESS!
Yes, they are my business but I realize that MY standards are part of the problem.