I do think there are a lot of modern psychobabble phrases for why it is OK to be selfish.
Now, if you are a doormat, you need to change that and close relationships should be based on equality. And, if you are making that change from doormat to equality, you need to talk about it, in this case with your husband. You two need to agree on what is reasonable or start divorce proceedings. There isn’t really a middle way.
But, no one can be their ‘authentic selves’ all time, assuming they even have this single self that they know is the authentic one. Most people make compromises to fit in with in laws or more distant friends. And, if they don’t naturally get on, they have shorter visits or try to meet somewhere more neutral some of the time. But, sometimes, you need to plaster a smile on and put up with fake bonhomie for a couple of hours. This used to be known as charm or plain good manners.
Ultimately, good long term relationships are based on compromise and, if you aren’t prepared to compromise, or the compromises are too hard, then you do need to consider whether you want to be in the marriage,
What if your ‘authentic self’ happens to be cross and grumpy? You can’t just expect people to accept the authentic you.
With this kind of situation, it is almost impossible to know where on the spectrum your relationship lies. But, if you make sudden changes to your character, you can’t expect people not to be surprised or not react. It might be for the good long term, but be careful of throwing the baby out with the bath water (unless you actually want to).