It's a Thin Line Between Love and Hate -- The Persuaders (1971)

 First day of Forensic Psychology:

It's a thin line, between love and hate

It's 5 o'clock in the morning
And I'm just getting in, I knock on the door
A voice sweet and low says, who is it?
She opens up the door and lets me in
Never do she once say, sir, where have you been?

No, she says, are you hungry?
Are you hungry, honey? Did you eat yet?
Let me hang up your coat, your coat, your coat
And the woman tells me, pass me your hat too
All the time she smiles, never once raises her voice
It's 5 o'clock in the morning and I don't give it a second thought

It's a thin line between love and hate..

The sweetest woman in the world
Can be the meanest woman in the world
If you make her that way, you keep on hurting her
She keeps being quiet
She might be holding something inside
That really really hurt you one day

Here I am laying in the hospital
Bandaged from feet to head
In the state of shock
Just that much from being dead
I didn't think my woman could do something like this to me
I didn't think she had the nerve, so here I am
I guess actions speaks louder than words

It's a thin line between love and hate..