Bg4 from queens gambit opening.

Hi guys, this is from one of my games. I am playing as white. 

How would you deal with this bishop pin? Is simply responding Be2 too passive? 

The exchange Slav basically gives white nothing to begin with. For your question I don't have a problem with Be2 as your setup is passive and the bishop don't really have a good place to go to anyway. Bd3 is possible but I don't see much benefit and I would be wary that like 5 moves later Be2 back may be needed and that would suck.

I've been playing the exchange because I was having difficulties playing against the slav and the different lines. I agree the exchange variation itself is too passive. 

I guess its time for me to begin studying slav and its variations. I was hoping to avoid memorizing lines. 

Black responded to your dull opening quite accurately. Quite honestly I would shake hands and head for the bar...