Kay, at first I thought it was about a guy being infatuated with a girl. But now it's obvious that it's about a guy murdering his girlfriend/wife. But I can see why I might have thought that way. "Why you just won't leave my mind" is the guy saying she can't leave his mind. "Was this the only way?" could be like him letting go of her and he couldn't let her stay in her mind because her memory would destroy him in his mind.
Kay, at first I thought it was about a guy being infatuated with a girl. But now it's obvious that it's about a guy murdering his girlfriend/wife. But I can see why I might have thought that way. "Why you just won't leave my mind" is the guy saying she can't leave his mind. "Was this the only way?" could be like him letting go of her and he couldn't let her stay in her mind because her memory would destroy him in his mind.