Pressing charges
"but realistically if he doesn't want to press charges over anything, which he really doesn't have anything to press charges over, then there isn't much the police can do (whether or not they have the will to). "
No such thing as pressing charges in the UK. You've been watching too many US cop shows. It's the CPS who make the decision whether or not to progress a case. The most a victim can do is refuse to co-operate which in effect the same as not pressing charges. But the victim can't force the charge through.