"Then shall He say also unto them on the left hand, 'Depart from Me, ye cursed, into everlasting fire, prepared for the devil and his angels.'" - Matthew 25:41
Jesus had just spoken well of those who respond to others with compassion and love in tangible ways. These are His disciples who have worked for Him by working for others. As a matter of fact, they have done these things for others, but Jesus said they were done for Him as well. These are those blessed at the right hand of the King (25.34). They are to come and inherit the kingdom prepared for them. They are blessed of the Father.
Now the King directs His attention to those on the left hand - the weeds ...the goats. They are not invited to come but are told to depart. One group comes to Jesus and another departs from Him - each to their eternal destinies.
The departing group is cursed. Their curse is to live forever in fire prepared for angelic rebels now known as Satan and his demons. There they are tormented day and night forever (cf. Rev 20.10). This is the awful reality of our friends and loved ones who reject our Lord and Savior.