A workaholic finds joy/satisfaction in getting work done.
They are hyperfocused on what they do and love it. Could autism be the reason?
When not working, they think about work and subconsciously crave returning to it.
Inability to work makes them unhappy.
Doing anything other than work is considered a short break before they can return to what they "live for".
As a result of their absence, their family and social lives suffer.
The partner didn't sign up to being "alone" in the relationship while the workaholic is absent most of the time. Over time, they become increasingly resentful of the workaholic partner and grow increasingly unhappy about the situation.
The kids are growing up with an absent workaholic parent. They get used to it but it leaves a permanent mark on their psyche (self-confidence?).
The workaholic sees things differently. "I will just get this done and then personal life can proceed." In reality it never does. If work ever gets completed, new work is necessary to give their life meaning/joy.
In theory the workaholic wants a partner, family, and social life, but in practice needs to work.