safe to assume that he had some kind of health issue. His Will is three pages, each written and revised separately over a period of months. I don't think a stroke would explain how his wife, his business partners and burial arrangements get left out. He is being aided by the clerk of lawyer Francis Collins and likely Collins himself and they are working from common boilerplate language and sections used in wills.
Scholars have suggested that the will was drafted in January (1616), then revised and partially redrafted on March 25 to reflect the change in the marital status of his daughter Judith. She married Thomas Quiney just over a month earlier, on February 10. At the top of the first leaf January is crossed out and replaced with March. On the same leaf, a reference to Shakespeare's son-in-law is altered to his daughter, Judith. On the second leaf a section making provisions for Judith "until her marriage" is deleted. Thus it is thought that the first leaf was entirely rewritten and then revised, and that the second and third leaves were merely revised.
https://shakespearedocumented.folger.edu/resource/document/william-shakespeares-last-will-and-testament-original-copy-including-threeHis relationship with Anne is documented as strained from the very beginning. Anne Hathaway was 26, pregnant and from a wealthy family when Shakespeare hastily married her. He was 18YO and his father's finances were more precarious, kind of boom and bust. Their first child, Susanna, is born six months after their November 1582 marriage. The twins are born in 1585 and named not for grandpa John or father William, but for Hamnet and Judith Sadler, neighbors. Hamnet Shakspeare dies in 1596 at age 11 and they have no more children despite having the wealth, time and social pressures to do so. The Shakespeare line dies out with childless granddaughter Elizabeth Barnard, daughter of Susanna, in 1670 so there are no direct descendants of William and Anne Shakespeare.
Travel between Stratford and London, about 100 miles, took about 3 days by horse or 5 days on foot. How much time they spent together is unknown but the assumption is they were often separated for weeks at a time.
More directly, and unexplained by health issues, is that Shakespeare took very specific steps in 1613 to prevent his wife from having any rights or claims on the Blackfriars property. And infamously, his last minute insertion of the line "I give unto my wife my second best bed with the furniture" can in no reasonable way be seen as commenting positively on the end of their relationship. The most generous interpretation I can fathom is that Anne's family was wealthy and she would likely have been okay without the houses, chattel, leases, tithes and money he leaves to Susanna. The most ungenerous interpretation would be that 'second best bed' specifically alludes to infidelity.
All of which is to say that ill health in early 1616 does not explain his emotional and physical distance from Anne as documented throughout their relationship.
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