Weapons, when they break and are mended, can be stronger at the mended places. Perhaps hearts are the same.
Cassandra ClareShe saw Valentine's eyes as the sword hurtled toward her; it seemed like eons, though it could only have been a split second. She saw that he could stop the blow if he wanted. Saw that he knew it might well strike her if he didn't. Saw that he was going to do it anyway.
Cassandra Clare