Talk to friend's (mean) girlfriend before talking to your friend
Q: A close friend has a new girlfriend. I don't like her. She's treated me with disrespect (talking about me behind my back) and she just doesn't seem to be a nice person. She's said some really mean things about people right in front of them. I'm planning on having a little housewarming party. Is there any polite way I can say my friend is invited, but I don't want him to bring his girlfriend when I'm hosting events?
You're Invited but Your Girlfriend Isn't
A: When she's said these mean things, you've asked her to clarify/apologize/step off, right?
If not, then you need to.
And if that doesn't improve the situation, then you tell your close friend you're concerned about some things his girlfriend has said. You ask if you're reading these situations correctly. You listen to his answer.
Then you give the girlfriend extra chances to show you why your close friend likes her, because that's what you do for close friends.
In the meantime, your party will happen, so invite her despite your reservations because that's also what close friends do.
Then, if you've dealt with the girlfriend directly; taken your concerns to your friend; granted the girlfriend second, third, nth chances to win you over; invited her to your event(s); and yet she's still mistreating you or others, then you get to say to your friend, "I'm in a bad spot because you're one of my closest friends, but Meanie has said awful things to so much of my guest list that she's no longer welcome at things I host."
Then you show concern for your friend because, if you've reached this point, how likely is it that he's spared of her abuse?
There's no renegotiating with Mr. and Mrs. Formality
Q: How do I renegotiate the terms on which I relate to my in-laws? I was an independent adult when I met their son; he and I have been married two years. I had hoped for a close relationship with them and put in the work to that effect, but it's clear they're not interested. They ask me to call them Mr. and Mrs., among other subtle things that keep me at arm's length.
While this makes me sad, I can accept that's the relationship we have. But … they call me "Dear," which makes me very uncomfortable given that it's obvious they don't think I'm a "dear" anything. How can I dial it back to "Mrs. Lastname" without sounding snooty?
A: "Dear" isn't confusing when you treat it as a term of patronage, vs. affection. My guess is you tried to relate to them as a peer when they were more comfortable with hierarchy.
Call me cynical, but when you say "renegotiate," I hear that you'd like to take another shot at getting the relationship with them you want. If that's your intent, then spike it now; challenging boundaries rarely endears us to anyone, but especially not to Mr. and Mrs. Formality.
The only change I suggest is that you base your expectations on what your in-laws are willing to give, as opposed to what you're hoping to get. Less food for resentment that way. Besides, from your brief description, it really does sound as if arm's length is their preferred distance, not just from you.