"I think you'll find you can." Snape replied, low and determined. "But overcoming the habit of a lifetime won't be easy and it won't happen overnight. I don't even need Legilimency to see that you're already feeling the emotions of anxiety, reluctance, guilt, regret, hurt intellectual pride... I can make a damned good guess, because I've spent my life understanding and using my own emotions, instead of vainly attempting to pretend they didn't exist."
He sighed. "Off with you, now. Go and take some time to think it over. When you're ready to be helped again, you know where to find me."