So to me this song is about someone who has lost a loved one because of his own inability to change.
He fells sorry for that and is only able to handle the pain by getting drunk. To stop his thoughts and everything. He knows that this behavior is wrong but hasn't found another way to cope with it jet. He wishes to stay in contact with this beloved person though he knows the other person won't love him like lovers do anymore (e.g. "so shall we speak then...").
So to me this song is about someone who has lost a loved one because of his own inability to change. He fells sorry for that and is only able to handle the pain by getting drunk. To stop his thoughts and everything. He knows that this behavior is wrong but hasn't found another way to cope with it jet. He wishes to stay in contact with this beloved person though he knows the other person won't love him like lovers do anymore (e.g. "so shall we speak then...").