The extent of David's abuse of Jane is revealed in Arthur's Alcoholic Atrocity, Parts 1 & 2. David beats and maims his wife when his beer is stolen, and he views her as his inferior. He demands that she slave away in the kitchen all day to make food.
David and Jane are seen in marriage counseling in Beats Me. Jane tells the "Marriage counselor" that David has been abusing her, unveiling and arm ripe with bruises. The counselor abandons their case, telling them that they're "beyond repair".
Later (in Arthur's Babysitter Drama), Jane tells Arthur that she and David have marriage counseling again, meaning that have continued the sessions.
After Buster murdered his father in Dear Diary, Part 4, Jane and David reluctantly agreed to take him in (Little Orphan Buster). By the end of Volume 7, they get increasingly annoyed at Buster, saying that he has overstayed his welcome (Buster's Savior).
David is fired from his job as a chef in David's Dead End, just in time for the holidays. This creates tensions between David and Jane, and it doesn't help that the grandparents are visiting for Christmas (Christmas with the Reads, Part 1). They decide that they have to tell the kids that Santa isn't coming this year. Meanwhile, both Jane and David's parents form an unexpected love connection, infuriating Jane (Christmas with the Reads, Part 3).