We all know that having close friends is good for you, physically, mentally, and emotionally. Your friends motivate you to work out, comfort you when you’re blue, and help you celebrate all the good things in your life.

But what about when they don’t? Sometimes, a friend can seem to do more harm than good to your health and happiness. Some take it a step farther by pushing you to do things you’re not comfortable with, or even things that are dangerous or illegal. So how do you dump a toxic friend, especially if you’ve shared so many good times together?

If your friend is pulling you down with a negative habit, like encouraging you to overeat, speak up! Tell her that while you love hanging out together, you’d rather not meet for dinner at the all-you-can-eat buffet, and suggest a different venue (preferably unrelated to food). The same holds true if she does something that makes you uncomfortable, like gossiping about a mutual friend; tell her, firmly but kindly, that you’re not cool with her behavior and you won’t participate.

If she gets the hint, great! But if the direct approach doesn’t work, you’ll have to decide how much the friendship is worth to you. A friend who knowingly drags you down might not be worth your while. You’ll have to decide just how much you’re willing to continue to put into the relationship.

If you otherwise enjoy her company, try limiting your time together. It’s okay to decline invitations to dinner in favor of group outings to the movies. And if she’s calling you for three-hour gossip sessions, it’s okay to cut her short by saying sweetly, “I’d love to chat longer, but I’ve got to go; I need to (finish fixing dinner, pick up my dry-cleaning, insert other excuse here).”

The exception to the rule is a friend who encourages you to do something dangerous or illegal, like drugs and brushes off your concerns. In that case, it’s fine to skip attempts to salvage the relationship, and simply cut off contact. It hurts to lose a friend, but when she’s hurting your health and happiness, sometimes, you just have to say goodbye.