I get why he wants to elave, he feels that Matt is betetr of without him, after all Matt has made a life without him, he wasnt there for Matt and Foggy thinks is better to o away than try to start things from scratch cause like he said there is always gonna be that cloud over them.
It's interesting what Kirstn said, the part where Matt still has feelings for Foggy-. They need to talk, Matt and Foggy and then the three of them (Matt, Foggy and Karen) maybe slap Foggy a little bit to put some sence into him.