You can learn a lot from someone by simply observing them.
I recently noticed in a particular relationship that the other person had very clear boundaries. It wasn’t anything that had been explicitly stated but through this persons actions it was very clear what they were and were not open to.
Sometimes a persons boundaries can feel personal. You might feel that they’re being harsh and closed off toward you. On the other hand you might internalise it and end up thinking you need to put in more effort.
In the situation I experienced I could have taken it personally, in fact 5 years ago I would have. I’d have thought this means [insert monologue of dramatic over reaction here] and maybe this person doesn’t like me.
But I now understand that a boundary is for the person setting them, it has little to do with the people on the receiving end.