Neither of those. It's the emotional burden that he imposes on my mom, making her manage his emotions because he has no other outlet.
In fact most of my male friends also don't get too deep in discussing their feelings. So it might not just be a lack of friendship, but a deeper problem which is men having a hard time discussing their emotions with others.
Correct. My dad is not angry with my mom or any particular person. He just gets cranky and grumpy if my mom doesn't socialize him.