So, let me get this right, it's OK for the OP to 'grab and pull' and dictate where her dp sleeps, but not for her dp to retaliate?
Yes. It is not ok to retaliate. It is ok for her to say her DP should sleep on the couch or wherever. I'm sure he knows what constitutes assault since he is a policeman. If he had a problem with what she did he should have cautioned her or called the police himself. He decided instead to throw her to the ground.
What you're suggesting is that he has a right to do whatever he wants despite her wishes. On a larger scale, most women who have been victims of DV have been accused of 'starting it' or 'provocation' and it is often asked 'why not leave?', why not leave your house or your bedroom, etc.
Just on a general level, being drunk is obviously a problem, but it does not excuse the sort of force that was used against the OP. Lots of people get drunk, men and women alike, and they do not get thrown to the ground or pushed against a wall. It is not the natural consequence of drunkenness.