Call them, they obviously need you.
Visit immediately, they need your help.
Txt them occasionally through out the day and talk about nothing
Call them around your friends on speaker so everyone can hear and make fun
Call them in a noisy environment around your friends so everyone can make fun and make them feel like you don't care
Brush them off like they don't exist
Claim your drunk and treat them like shit
Tell them to figure it out, your old enough by now
Keep your plans but make it a point to visit