Not to be cliche', but there's nothing that can't be cured by eating ice cream out of the carton with a friend.
Front: "Let's eat ice cream and talk about it"
Inside: Blank (for your warm, heartfelt message)
LET'S EAT ICE CREAM AND TALK | CARD
• 4.25 x 5.5 inch folded card
• 100lb white paper
• green envelope, size A2
• packaged in a cellophane sleeve and mailed in a rigid mailer