tofu

"""係咪萬一配偶第時同你離婚，到你百年歸老嘅時候，都冇權分你違產呢（GIVEN佢地冇名係平安書上分錢）"""
i believe you mean separated before pass away.
-depends on what, like pension, the separated spouse can still share.
if spouse gets the support payment, the spouse can ask to share the estate.
but remember when they are separated, she needs to give 50% to him lor wor.

give all the money to someone else, but if he knows it, he can request court order to stop it.  he can say that you guys cheating on her and .....  the thing is he can say they have been together for so long and he contribute time and effort to this "family assets".  
not sure how much money you talked about, but she can set up a trust, give him so much per month for living but after he is dead, the rest of the money go to someone else.  and pick someone else as trustee which he has no control of the trust.  if she doesn't has anyone in mind to be the trustee, she can get the bank to do it.  many financial institutes have estate & trust service.
she can ask a third party(accountant, lawyer, financial planner or bank....) to be the executor, which you guys don't need to deal with him, of course there is fee la.
fee for set-up a will is $100+
in this case, i will suggest her to set-up a power of attorney now.  prepare the time she can't mentally or physically manage herself or her money.  if she didn't prepare, the count will probably give the control to the spouse or public trusty
in the worst case, no matter what you did, he will fright for money, which most of the money will finally go to the lawyers' accounts.