Not Moving In - Double The Stuff or Lug It Back And Forth?

I have always been the type of girl that likes her own space. I've posted on it, I talk about it, and on date 10 or so I generally bring it up to anyone I'm seeing in case they think that someday I'll be the type of girl that likes to move in.
Not that I won't, just that I don't really like it. For example, I moved in with a boyfriend several years ago and told him that his closet would have to be in another room since all of my clothes were completely filling the one in the bedroom. He took his arm, SHOVED my clothes to the side leaving a foot or so of empty bar space and said "yeah there is, look!" He made it one month after that.
So now, I'm dating the New Jersey-ite and we had talked about moving in but I have a lease that goes for a few more months so he decided to get his own place. Fine. Great.
But it's disrupted the flow of things. It used to be that my place was much nicer so we spent a lot of nights there and he brought a lot of stuff over and everything was all good.
Now, he likes his place a lot so I have to go and buy another set of stuff to put over there.
Girls back me up on this: If you are splitting your time between 2 apartments you are either lugging a huge bag back and forth, sometimes forgetting things you absolutely NEED or you are buying a whole other set of stuff.
The case for back and forth - this is certainly more economical than buying 2 sets of everything. I am a fan of nice hair equipment (straighteners, dryers, etc.) and face products so buying two would be a major investment and if we ever do move in it would also be a major waste.
On a very pessimistic note: less to pack up if you break up.

The case for doubling up - much more convenient and I can have a small purse vs. the massive Urban Outfitter bag (which I love but am sick of now). Also, you have less moments spent looking for an item that you left at the other house.