cowards and how I hate them

Let me put it to this way, if you are in a relationship and have been in a relationship for 6 1/2 years then you dont leave the person by leaving a note. This happened to a family member of mine and I have to say its the most cowardly move I have ever seen in my life. You lived with and loved someone for 6 1/2 years and you can just write them a note and say I love you so much and care about you but not in love with you and leave while the other person is at work. How can someone do that to someone they said they love and wanted to spend the rest of their life with? I understand that people fall out of love and people break up for many many reasons that I dont have the problem with, I have a problem with how it was handled. It is taking me writing on here about it to keep from calling or texting or emailing him and telling him just how screwed in the head he really is. I have never seen this family member devastated like they are right now. He not only lost his boyfriend he lost his best friend and that breaks my heart.
I really thought I knew this person, he has been a part of our family for 6 1/2 years, he has been through a lot of stuff within the family and I feel that he turned his back on all of us by deciding to leave the way he did. How does he think that made my brother feel? It made him feel that he meant nothing to him and that the last 6 1/2 yrs did not mean anything to him either. It just makes me so mad that I cant even think of what to say anymore.