What you think is pseudo, probably isn't. If it were all pseudo, you wouldn't be cleaning it further, right? You say you lost half of your pseudo, but what you really mean is you lost half of what you thought was pseudo.
You can cover pseudo HCL in xylene and bring the xylene to a boil without dissolving any significant amount of the pseudo HCl. You didn't lose half of your pseudo to xylene, hot or not. You had something in addition to pseudo in the mix. If pseudo HCl were that soluble in hot xylene I would have noticed yield loss associated with such boils long ago. Additionally, I have done a/b extractions of pseudo from pills after xylene boils, and without xylene or tolly boils, and have never noticed any appreciable difference in yield.
Its not the xylene. Its most likely that your pseudo isn't all pseudo.
Beyond that, you should be doing the xylene boils of the entire pills mass, not just the pseudo. If you are extracting the pseudo first, then trying to clean it with xylene boils, you are actually making your task more difficult, not easier.