There is an excellent BBC YouTube Clip about "inside Henry VIII's Body" with the always interresting Lucy Worsley. They do talk about his several illnesses and the effect that some of the immense pains should have on a body. https://www.youtube.com/watch?v=3ofdjTzZRm8
I think Henry's older brother Arthur married Katherine of Aragon for political reasons; Henry however, I have always gathered, did it because he genuinely loved or liked her (and the allience reasons still stood).
By all accounts Henry and Katherina had a very good marriage for almost 15 years which is longer than most marriages lasted in those times (premature death didn't grant everybody a golden wedding anniversary).
I think Henry in his middle-ages (as many men!!) started to have a bit of a Midlife-crisis: his entire world- and self-image was deeply anchored in this powerful Prince image:
The best in battle, the tallest in the country (he was extremely tall for his time) the best looking, the best in every competition - he was
Britain and Britain was only as strong as his powerful prince.
Yet this powerhorse simply could not sire a son and heir...and at a time when you looked to the above to explain things, he came up with rather weird answers. He wasn't the first (or the last) to dispose of a wife, who couldn't bear him a son, only quite possibly the most awkward and inapt.
His whole personality changed drastically after the accident he had while already married to Boleyn, I think this is the turning Point at which he started going mad.