This is a great post, but i believe people can become TOO strong post-breakup after they get over-it, especially when it's time to meet new people. What i mean is you have many jaded and disruptive personalitys post-breakup that when you meet someone new and start dating, they may have flashbacks of similar happenings and their strong and protective instincts from the past kick in either causing the other person to feel rejected or confused.
Really the best way I can describe it is like in Star Wars. You have the good and dark side, both posses strengths but one chooses to use it for bad and the other for good. Now i'm not saying you are going to Darth Vader the next relationship, but you may take some anger and resentment into it when something similar from the past which happened during the relationship /break-up, and that my friends is where the good strength needs to kick in.