This may belong in a different SE site, but I wasn't sure which is the best one.
Background: I was diagnosed with ADHD as an adult last year. I'm still working on getting the correct amount of medication ironed out; things are better, but not quite there yet, wherever or whatever "there" is. One of the lingering problems is that I still struggle with sustained mental effort. If something doesn't immediately come to mind, then it feels like I'll never think of it.
Additionally, I don't have strong opinions on a lot of subjects and I want to be accommodating, because I have the tendency to be...self-centered is the closest thing that describes it. It's not that I'm thinking only about myself, it's that it doesn't often occur to me to think of other people. This frequently causes problems of one sort or another between me and my wife: we have a happy, loving marriage, but quite often I will do or say something that is incredibly insensitive or selfish, causing her emotional pain.
The self-centeredness is something of a separate issue, although it's almost certainly related.
Additionally, I'm a recovering addict. In my opinion, all addiction is the same, so the specifics aren't important, just the behavior archetype.
How this relates is that I have an automatic self-preservation mechanism that manifests as a "say what needs to be said to not get in 'trouble'" response. Often this means that I'll say some part of the truth to avoid out-an-out lying, but withhold something that could change the dynamic of the conversation.
Finally, I HATE confrontation, to the point that even the thought of it gives me physical discomfort.
Behavior I wish to change: in an effort to be accommodating and/or to not upset the apple cart and/or avoid mental effort and/or some other factors that I'm not considering, I will often immediately say the first thing that comes to mind. This likely is an offshoot of my desire to be funny, so I have to be the first one that comes up with the joke, before anyone else does. Often, this takes the form of what I think that the other party wants. Because I don't have strong opinions on things, I will suddenly "believe" what I'm saying; this allows me to fool myself into thinking that I'm being more honest than I actually am.
I don't know how to slow down and not do this. It feels like I have so many emotional and/or mental issues that I can't pull at one thread without the entire thing becoming unraveled.
My wife is the exact opposite: her anxiety is so strong that she's paralyzed with indecision because she doesn't want to offend anyone, so she has no idea how to help me because she can't understand my mental process (I don't blame her or resent her for this; I don't understand her issues any more than she understands mine), whereas I struggle with indecision because I don't want to make the wrong choice.