AI most definitely. I came away from that thinking life meant nothing, since you always end up losing everything you love. Not exactly a feeling that inspires you to get up in the morning.
Also I had the pleasure of watching Marley and Me on a flight from London to Hong Kong. You could tell who was watching it by the sounds of sniffing. One woman was even sobbing.
Me? I turned it off at the point where Owen Wilson lay down next to him by the fire. If I'm going to blub like a child I'll do it in private thanks 😛
(and yes, I did blub like a child when eventually watching how it finished)