It's back to basics with the old 'Dog Psychology'!!
You have to build their confidence whilst not being perceived as a threat.
Even if you reassure your dog when they have made a puddle is stressful to the extremely submissive dog.
Trying to reach for your dog to prevent a 'submissive episode' on your silk rug is a threat!!!, they just release more and more urine as a way to show you that they have low levels of testosterone (which is why this problem is more prevalent in Bitches than in male dogs)
You have to show NO reaction to this at all. Just walk away and ignore it.
Very difficult, believe me!! I have always had large breed dogs and you have to employ exactly the opposite behaviour with them, so it really was a break from the norm for me.
You have to play games with the dog..such as tug of war...and let them win...it's about building confidence.
No eye contact, that was another important point. That's a threat too!!
But it really works, I have a happy, confident little yorkie now. He's always going to be slightly nervous and submissive, but the plus side is that he display no aggression at all - that was my most desired trait as he is chief companion for my four year old daughter, who wanted a brother

, so she got a little Davey man instead!!