Grace and forgiveness and repentance can come in stages. Sometimes, realizing there is something we need to cut out of our lives - whether it be a desire or an action - is a long, slow process, and there is always grace through the process.
That said, ensuring that you do not fall back into that thing is vital, and although it can sometimes be extremely tempting, know that it will not enrich your life in the long run. This in itself is a form of obedience, a form often more nuanced than it appears. There's always grace!
"As obedient children, do not conform to the evil desires you had when you lived in ignorance."—1 Peter 1:14 NIV | 
