I also raised my fees, so that now I will only discuss projects at a minimum of €10K. It definitely helped shift some of the crap :)
Ask yourself is this increase of work temporary. After all current deadlines are met, will you still be as busy? Can you expect to relax and rest, or are you expecting as much new work waiting for you? Will there be as much work two months later? six months later? Will there be more work? Will there be new clients?
If it's not temporary, if there will be only more work, then it's only reasonable to focus on seeking help now. You can't handle the workload you can't handle forever.
You probably need to change your mindset too. From "what do I need to do to solve this problem?" to "what help do I need to solve this problem?"
I recommend reading E-Myth Revisited, exactly the book for small business owners facing too much work to do.
Obviously it didn't turn out very well for my friend as he didn't really get do much. I suspect the owner however might have learned a thing or two about managing people.