Sentence:  It&#39;s a <WSD>heartbreaker</WSD>. The worst part of that situation was trying to console Grace. It was just awful. Don&#39;t let experiences like this make you bitter. The truth is, our kids are a challenge, and not everyone is going to want to join us in this journey. 
Meaning of the word marked with <WSD> tags:  Something that causes sorrow, grief or extreme disappointment.