Are they having marital problems?

This situation doesn't seem right to be, but I'm not married, and so I seek your thoughts, please!

My aunt and uncle have been married for 40+ years. My uncle is--to put it nicely--a jerk, in my view.

My uncle has started spending time halfway across the country in an RV, in the same location for now months on end. My aunt and cousin have traditionally joined him for part of the time, and his guy friends join him for other times.

Last year, he and my aunt and cousin went to the RV. My cousin let me know that my uncle was mean to her and my aunt and was a "total buzzkill" during the trip.

This year, my uncle is spending 4 months in the RV. My aunt is spending just 2 weeks there. My cousin isn't going at all.

My mother asked my aunt if she's sad or glad when my uncle is gone. My aunt answered, "that's a loaded question" and didn't answer.

So...is my uncle having marital problems? Or are there other problems here? Seems odd to spend 4 months mostly away from family.