Jerk off several times a week. It significantly affects your mood. You know how you're grumpy when you're hungry, well, guess what?
Learn how to express your emotions effectively. Don't try to cowboy your way through emotional struggles. The most chill dudes are ones who are masters of this. You'll live longer too. .
Sometimes when your girlfriend is freaking out at you it's because you're not giving her any response and she's panicking. Say something...anything. Looking away or out the car window in silence while you try to figure out what to say next never works. An easy approach is to say "I feel..." and say how you feel about whatever it is she's mad at. Even if you don't feel anything or know what the fuck she's mad at. Say that, then. Say something. If you sit there and hold your cards, you're going to risk exploding as she keep spinning her wheels and that doesn't help anyone. Believe me, as awkward as this is, she probably just wants to know how you feel because she's worried. Don't wait either. Some of the biggest regrets we have in life are the things we should have said when we had the chance. I have about 4 of them on instant replay in my head. They will be there forever.
Imagine you're on a road trip from hell. Would it be better or worse if your SO was there? How you answer will speak volumes about your relationship.
To avoid the "mansplaining" situation/label. Pose your statement it in the form of a question. This works most of the time (depending how your frame it) and questions can sometimes connect you better than statements.
"Nobody in life gets exactly what they thought they were going to get. But if you work really hard and you're kind, amazing things will happen." (Conan O'Brien)
Most people don't care about you and that's not something you should concern yourself with. Live your life for yourself and those you care about. Spending energy trying to impress or not look foolish in front of total strangers is a fool's errand.
Sinking ships and divorce/family court share the same priorities. It is what it is. Be prepared in these kinds of scenarios.
Own your missteps. Being defensive is how you avoid growing. This will also zap any tension away if it's a social misstep. It doesn't mean you're wrong, it means you're trying to figure it out. You're only wrong if you give up and blame the other person right away. If they don't let you off the hook though, fuck'em. You tried.
You're probably gonna have to kill spiders and check out weird noises in the middle of the night. Keep a Louisville Slugger in your closet and a decent can of bug spray at the ready if you're too queasy to squash'em with a tissue. Buy a kids bat. They're smaller and easier to wield indoors than a full size bat.