he is married--to his job.
what you saw with his revulsion towards "intellectualism" is his wanting for something that hasn't saturated his experience for the past 20-something years. he's in his 40's, so he may be closer the whole "mid-life crisis/what the hell have i been doing with my life" which is how you could get the behavioral extremes he's showing, which would match up directly with his dominant and inferior functions.
from what you've told us about what he's told you... he's led a very un-balanced life and reaping the benefits/downfalls of such. his job, this thing he can get lost in and make total sense of, could be and sounds like it is the source of his own discomfort. he's traveled a route that easiest for him to the detriment of the side he naturally, consciously ignores. he's brought on more and more responsibility... why? he doesn't sound to be enjoying it... it gave him a heart attack--that much stress cannot be fun, but one would first have to realize that they don't enjoy it before it can even register as "not fun". maybe it's an attempt to distance himself from the direction he would naturally move towards (again, the side one has to ignore in early life, the mindset that is the inferior), and in some way he realizes this, but even though he would like to have what he should in order to re-balance, he's backed himself into a wall, realizes it, and with that realization he knows that what he would do to you would be his broken marriage all over again...?
so, he did the sensible, fair thing--if he knows that he can't/won't make a change within himself, he breaks from you in order to save both considerable pain and wasted time.
--side note: not all INTPs are deficient, robotic creatures devoid of human expression. they just operate within that part of themselves differently than others do. and at INTPCentral... never been there, but from what i hear it's comprised of angry high school virgins who hate the world (see, immature/lack of perspective)... not a good representation of the INTP-image, i'd think. there are plenty of INTPs who are nothing like that... one has to remember that what one is seeing is never the totality of what there is to see. (this last part isn't directed at you Darya)