Your man is a traditional man, being relatively
conservative in his approach with affection and appreciation. Man
like him tends to display a 'reverse' order in attitude towards
their relationship as they generally buy the self belief that love
means having to discipline... the way parents do to their child and
tell them that's love for them. They will probably relate this
typical story: 'If I didn't care for you, you think I even bother
to scold you?'
The traditional man also sees himself as the provider and his
ability to provide comes from his career. He may seemed nonchalant
when it comes to his work, because he's fighting a war out in the
corporate world, attempting to improve his market value, job
prospect, salary, promotion, learn new skill sets and everything
else that could give him any form of opportunities to become a
better provider in the long run... insofar as to be able to provide
a better life for his SO (significant other) and his future
kids.
Unfortunately, in that perceived 'near-perfect' macro picture, the
traditional man often omits the finer brush details and neglected
the woman's emotional needs. And if he subconsciously decides that
the length of the relationship itself, which is actually false
pride, could surmount most challenges, that sort of mindset could
cost him a hell of a price to pay.
There are times when a woman would be equally happy even if their
man merely sits with her, while watching her favourite show
together and devouring that tub of ice cream.
I won't say that Y is definitely a viable candidate for you to leap
ship, but surely, he enlightens your long-suppressed heart and mind
by revealing the frustration you experienced in your current
relationship.
Would you have faced this conundrum if your relationship is
blissful? Not likely or at least you wouldn't be so affected.
Looking deeper; why is your relationship so unfulfilling for you?
Is it because you are NOT communicating enough to build that basis
understanding and expectation of what a relationship should be
like? Chances are, your man has no idea of what you are feeling
absolutely, despite leading the relationship for five years, as it
appears to me like you are very accepting about the unnecessary
evil that is causing your unhappiness.
It would probably be worse if his parents are exuding such
qualities as well - those sublime early childhood influences might
just linger far too much.
Before you execute him from your life - give him a fair trial. At
least, imho, if your situation improves, you might still want this
relationship ultimately. Date him out and give a solid
heart-to-heart talk. Make this matter a known case and at least see
if there's a mutual agreement/solution to resolve it. 
Cheers
