I believe that my late alcoholic boyfriend was capable of feeling love and loving me in return, but with an alcohol-clouded mind. I've learned that it's safe to assume that an active alcoholic is always under the influence of alcohol. Imagine trying to understand the often subtle messages and complex emotions of love when your mind is saturated with a toxic substance. Love is hard enough to figure out with a clear mind.
So my answer is, yes, an active addict is capable of loving others, but in a more limited capacity than I needed.
Sharing a life with an alcoholic is emotionally and physically draining. It's not just hard, it's darn near impossible. Because of this, I tended to judge my boyfriend too harshly. He was, after all, just a man. He was never the prince charming I had blown him up to be in my mind. And while it was easy to blame all the chaos in my life on my boyfriend and his drinking, I eventually realized that he was not holding me hostage in that life. I was.
A new life was always there for the taking. All I had to do was let go of the things that weren't working for me, and walk through the door.