It all boils down to our childhood. Negative emotions and the inability to communicate them in a loving way is a reflection of the amount of unresolved childhood emotions that someone carries.
It doesn't matter if you have 0, 1, or 2 parents. While 2 parents have a greater chance of success, most parents fail to validate a child's feelings and provide with the resources to successfully communicate lovingly with a partner. There is a bigger emphasis on validating a child's feelings these days, but it is certainly still a minority.
Look at the guys here and you will see an abundance of unresolved childhood trauma.