What do you suggest one does when a couple is fighting and one partner tries to leave the room to go cool off, and the other refuses to let them leave? I mean physically blocks the door and tries to continue talking about the issue at hand?
I ended a long-term relationship with a girl I absolutely loved, because I repeatedly felt claustrophobic in this exact situation. I'm twice the size of my ex and when things would get really heated, I felt trapped, because if I pushed her away, then it's abuse, but if I stayed, I felt trapped and would get even more agitated, accomplishing nothing.
After several times of this, we agreed that she'd let me go cool off when things got heated, but to no avail. She still blocked the door the next time it happened and I abruptly ended things.
I'm wondering if it's acceptable to leave when you feel you've reached your limit, or if I'm in the wrong and need to recalibrate my perceived need for space. If so, what do you suggest for calming myself down when I feel I'm at my limit?
Answer: When you reach your limit in an intimate relationship, there's no one right way to handle it. There is merely a range between inappropriate extremes. The extreme on one end is withholding - shutting the other person out completely. Silent treatments go in that file, as do the refusals to listen to or discuss certain things. At the other extreme is violating the other person's body, boundaries, or autonomy, which includes blaming as well as verbal and physical abuse.
Your ex-girlfriend went to the latter, abusive extreme in blocking the door. You were absolutely right to flag it as something you wouldn't accept, and to break up with her when she ignored that limit - especially after you had just discussed it.
Your tactic of leaving the room to cool off is in the appropriate range between those two extremes. Ideally, you spell out your intentions as you go - "I need to go calm down, then we'll talk again" - because merely storming off would be a form of withholding, but, even then, temporarily removing yourself from a heated situation, even without comment, is still preferable to staying until things explode.
So, no, you don't need to "recalibrate my perceived need for space." But the problems in this ex-relationship weren't just about that, but instead the frequency with which you found yourself needing said space.
Love is highly individual, but I find it hard to imagine "absolutely" loving someone with whom I disagree so fiercely and often. Not in a mature, adult relationship.
Which leads me to believe either that one or both of you lack the maturity to sustain an intimate relationship - or that what you share is not love so much as a passionate attraction, one that only partially compensates for serious incompatibilities.
So instead of recalibrating your need for space, please consider recalibrating your idea of a loving relationship. Volatility isn't a sign of passion, it's a sign of problems. While some people have a high tolerance for volatility - again, love is highly individual - your whole letter suggests you don't. Please consider that the woman you ultimately, absolutely love will involve far less to argue about.