The issue becomes as big as you want it to become. If you will think too much over it and make your mind before hand that your personal space is more important to you than your friends then why make friends in the first place? Why bring people in your life only to block them out later? Just alienate everyone and be a shrew.
Sometimes people forget that since we are human beings, there is such a thing as emotional attachment. Sometimes the people you are close to, you do get emotionally attached to them. I think sometimes people mistake this for being possessive. This is when the whole speech of “I need space” comes in.
No matter how annoying some of my friends are or how possessive some are, even to the extent that sometimes I feel claustrophobic, I never gave them ultimatums that I am going to kick you out of my life. I don’t have a right to do that. I don’t have a right to cause hurt to someone. I don’t have a right to make them sad and depressed. No matter what, when friendships break, people are affected by that. I can’t see that happening to someone because you know why? I can’t see that happening to me. The way you are with people is the way people are with you, just remember that for life.