Want to help friend suffering from depression

hello there is this best friend of mine she together with one more friend of mine we were almost like siblings , but 3 years ago she deleted everyhitng and she was just gone i tried to reach her but she didnt pick up my calls, Now 3 years later she called me today and she was sorry about what she did to me and our friend and that she was going thru very rough times , She is still depressed now , I want to help her but i am so confused cuz she is a total mess emotionally , she has no friends in the college and she even has started to draw herself away from her family , i want to help her so if there is anyone who has faced similar stuff please tell me , she wanted to commmit self harm but stopped herself 2 years ago but she is still mentlally depressed