I recently got a deal where I bought a complete Jabba's Palace and Rancor set for $50.  Sometimes I'm relieved when I get a good deal on loose sets that I want to build.  Knowing that I don't have to open a sealed set that might be a good money maker down the road is a great feeling and I'm not sure why.

I would suggest storing your LEGO sets out of sight, to get rid of that temptation. If you enjoy looking at the sealed boxes, you could always purchase one to build, and one (or more) to store away.

I also find buying used lots can help curb the desire to open and build boxed sets.

All you have to do is find one really big bulk lot, and that should keep you busy for a while.

I always buy used sets, it's a cheaper.  Sometimes I buy used + incomplete sets and then complete the set myself, it is even more cheaper. 

I found it very difficult to crack open a big set like SSD or Crawler 41999 when the set has a lot of potential.