Perhaps you've never met a narcissistic psychopath. There are actually quite a few out there, more male than female.
In my opinion, most socially negative behaviors have their root in insecurity and low self-esteem.
An Alpha, by definition, has high self-esteem and doesn't need to keep a woman under his thumb because he knows he can always go out and get another woman. He has an abundance mentality, not a scarcity mentality as a Beta would have.
It's only when consent is taken into the factor. in Animal kingdom Alpha goes around killing rival males, and keeps all the females to himself by force, in human civilization they can use power, influence, and manipulation, for instance powerful men who sexually harass younger girls. So being alpha doesn't mean they have high self esteem, confidence, and doesn't keep women under their thumb, it's a false belief. According to the dictionary definition, alpha means simply "describe someone who is strong or powerful, and who likes to be in charge of others:" . Alpha has more power, influence, and control over their subjects, and also is willing to be in charge of others. Alpha might be insecure or not, Hitler, Churchill, Stalin they all had insecure sides, but they were very influential, and powerful in their domain. Insecurity means according to the dictionary definition "a feeling of lacking confidence and not being sure of your own abilities or of whether people like you :" So Being alpha or beta is nothing to do with the insecurity. In fact betaman tend to be more insecure than Alphas, but Alphas can be insecure too. Alphas who insecure tend to be more paranoid like Stalin, and ruthless in fear of a riot or opposition because they are not sure they can compete with their rivals. Also alpha, beta are relative terms, you can be strong, powerful and likes to charge others, but in front of another alpha you might not interest in it out of fear or insecurity, a good example for that is Generals in a military. They are beta in relative to the Monarch, but in relative to their soldiers they are alpha, but still certain traits like confidence, self respect can be seen in some alphas even if they are beta towards their superiors. However, generally speaking betamen tend to have no self respect, have lack of confidence, insecure. The abusive men who harass their loved ones can be alpha or beta. Alphas can harass their loved one out of jealousy, to demonstrate his power, not necessarily because of the low self-esteem, but they can do too. Betas on the other can abuse their loved one out of low self-esteem or also to demonstrate his power. There are no absolute betas or alphas as I explained above. A beta might be alpha towards weaklings, but can be beta in front of an alpha. Alpha, beta terms are for power, and influence. All in all there is no correlation between Alpha and high self-esteem, insecurity. And please don't quote one line and comment on it, then it looks like out of context.