To love someone in spirit IS to love them despite what they do. It sees THROUGH what they do and makes no conditions based on what they do. Basically to love someone in spirit means that we see them as a child of God, blameless before God because of his Grace.
Imagine if I was blameless, never did things wrong and was thus worthy of great friendship from everyone. It would be very easy for you to love me. But that is because I would not have horrible things in your way. I wouldn't have the habits you hate, the struggles you strike out against. I wouldn't do things you hated. Now if you see my habits, my struggles my flawed HUMANITY, it is harder to love me, but you're looking at the wrong thing.
The only reason God loves us unconditionally is because he doesn't even see the things WE base our conditions on. God does not see my habits, struggles and flawed humanity. He sees, "a little child who hasn't been loved enough and who has ceased growing because someone has ceased believing in me." Now if I could love others that way, I love them in spirit because their flesh makes no difference to me. I could care less about their flesh, their struggles, their habits, their hangups and flawed humanity. I love the child who needs someone to believe in him, the spirit who truly is blameless and incased in a flawed human flesh.
When I used to go Perkins in college (Oh how I miss Perkins), I purposefully never saw a waitress as a waitress. I saw her as a person like me, not a person there to take my order, bring my food, end of transaction. She was a person, a child like me who needed someone to believe in her and treat her that way. I loved the Perkins waitress in spirit not flesh, because I did not care that one of them had been divorced 4 times, cussed like a sailor, and had three kids from different men. But I do know that she wept in my arms one night when she was terrified and broken. I loved a waitress in spirit instead of her flesh.