Of course, the original letters can be found here.
LW#1: There is seriously a formula to at least one letter each week, and it goes, "S/He's great, BUT." You are apparently that LW, who, after literally years and years of advice columns, has not gotten the message. The message is that the "but" is something you'll either have to learn to tolerate or decide if it is worth breaking up over.
Sometimes these "buts" are things like, "he is getting fat." That sort of "but" reflects on the LW. Others, like, "he plays footsie with his sister," are a little more ambiguous, like, "You see this as a red flag but you're engaged anyway?"
You, however, have written in with one about a guy who violates your boundaries. Daily, even! You tell him you don't like what he's doing, and he tells you obviously you're wrong because you're laughing. Let me walk that back for you: You are pinned under him, he is doing something you don't like but to which you have an involuntary reflex, and he's telling you you must like it. Moreover, he's telling you that once you "master your mind" you "won't panic" when he does it, and he is going to do whatever he goshdarn pleases.
This is not a good dynamic. And written like that, it sounds kind of rapey, doesn't it? At the very least, he's giving you a mind(freak).
Just that what he's doing is a violation. And although you haven't said how long you've been with him, if he refuses to get that what he is doing to YOUR BODY should be at YOUR WHIM then he is either due for a dumping or a serious session of counseling.
What he is doing is flat-out unacceptable. And you need to accept that.
LW#2: Wow, fun birthday celebration. "So those years I was checked out in an alcoholic stupor, what was on your mind then, sweetie?"
Yeah, this is one of those situations where she probably doesn't realize the import of what she's asking. Chalk it up to years of brain cells marinating in Night Train (or whatever her booze of choice was). She probably realizes intellectually that those years were rough, but hey, being kind of insensitive and selfish are personality traits one kind of needs to be a totally checked out mom. (As of now, she sounds like she's still a tiny bit checked out. I mean, seriously.)
For now, you can probably just say, "Mom, that's a lot of history, a lot of pain, and I can't imagine hashing it out with you at all right now, much less at some lunch in a restaurant." I wouldn't get into it or get dramatic with it, I'd just state it as fact and move on. If she feels the need to know more, or let out her feelings, she can do that with her sponsor.
Honestly, you don't owe her anything of the past. She owes you her respect.
LW#3: Once people partner up it is really hard to not invite their partners. And when they have kids, sometimes those kids will come along, too.
The only way to have a party without partners is to specifically have a gendered occasion. Seriously. "Girls night y'all!" "Boy's night in hizzouse!" So if you can swing that because you and your friends are one gender, you can do it.
The other possibility is that you make this a non-sit-down affair and use your table as a buffet and everyone hangs out in the kitchen, dining space and living room and meanders. Move the chairs out to the living room, etc. Then it isn't the table that is the problem.
Besides, 10 people for a sit-down dinner is too many.
Also, to address this: "I'd just hate to forgo inviting friends I'd like to see in order to make space for significant others who aren't significant to me."
If these people are significant to you, their partners are now part of their lives and you should make an effort to make them significant to you. If you don't, you will find yourself losing significance to your friends. Just a thought.
LW#4: You did something few people do, and you are handling it in a way fewer still could manage. You are awesome.
But now it's time to listen to your daughter, and let her needs and feelings guide this process. That's what open adoption is all about, right? The affect of family meetings in concept and in reality are two totally different things, so worry less about what will happen if you don't adhere to the concept for its statistical and theorhetical benefits instead of what is happening's effect on your daughter.