First of all, you can think about whether there is a logical mistake in your thinking - to spread a specific puzzle into a more complex conceptual problem.
Its very likely that the break-up is due to problems on both sides, more of which is the lack of matching.
But she may raise this specific problem to a more serious level, even involving self-concept, am I incompetent? Or cant I handle intimacy?
This is a logical mistake that many people will have. Like you mentioned that you have met with an emotional setback recently, it may just be an emotional setback.
What you need to solve is just this specific problem, not to complicate it into sense of distance and not dealing with people.
Using more complex and huge concepts to examine specific problems will cause more problems.
Second, after thinking about the first question, lets talk about another possibility, that is, you really have a sense of distance with people and cant dig your heart and lungs.
Is this a very normal state of mind?
Just as we are nervous when walking at night, and even prepare prevention tools in advance, this is the embodiment of human instinct and security needs, not a problem.
Third, if this self-protection boundary is excessive, it will indeed be called a problem.
How to call excessive? You can evaluate yourself.
Its that you are really eager to talk with others and establish a completely undivided connection (which is too idealistic in my opinion), but you cant do it, and you feel uncomfortable because you cant do it, which affects your normal interpersonal communication.
If this level is reached, it can be called fusion anxiety.
Syncretic anxiety is a kind of fear in ones heart. Fear establishes a connection with others, because subconsciously they fear that the connection will lose their integrity and independence.
At the root of it, because there is no complete self, there will be this fear.
Self is too fragile, so we should build a thick wall to isolate others and protect ourselves.
Looking back, why do fusion anxiety arise?
Because from small to large, your real self has not been seen, affirmed, your feelings have been ignored, your complete self has never been shown the opportunity, so you learn to hide (again, the integration anxiety is a very extreme situation).
Finally, back to the action level, you mentioned that you want to change, and the change in action needs to be guided by the change in the cognitive level, so the integration anxiety mentioned above needs your reflection, understanding and internalization.
Besides cognitive adjustment, what else can you do?
You start to discuss your confusion with your friends and get feedback from your friends. Its already you showing your inner world to others, isnt it?
Because in this process, you not only open your heart to let others see you and understand your feelings, but also constantly revise your self-consciousness and pay attention to the real self.
You already have the power to change, keep it, keep it!