You hear about the male mid-life crisis all the time.  It conjures up a pictures of a slightly balding guy wearing gold chains driving around in a convertible.  Seems kind of cliche and almost funny.  However, it is not funny if this is your husband or lover.  His mid-life crisis may have quite the ripple effect.  The causes of this condition are many.  They could be physical in nature.  The changes in his body might make him slightly uncomfortable.   He could be a little depressed.  Perhaps he feels unappreciated and restless.