I Moved In With 2 Other Girls Into A Furnished Apt. In Honolulu, Hi Over 3 Years Ago. One Of The Roommates Moved Out After 1 Year. My Boyfriend Moved In. She Was Scared To Ask Him For Her Share Of The Security Deposit So She Left & I Am Not In Contact With Her Any Longer.

The Second Roommate Left & Also Did Not Ask For Her Share Of The Deposit. I Now Have Recently Moved & Got Back All Of The Security Deposit & Would Like To Share The Fair Amount With The Second Ex Roommate.

I Do Not Know The Proper Or Just Fair Way To Split The Money & Or If I Am Legally Obligated To Find The First Roommate To Give Her The Money Back.

Aloha,
Kim

Legally obligated--probably not. I don't know HI law, but I doubt that you have an obligation to try to find them.
As to splitting the deposit, each person is entitled to one third. So if you want to share with the second room mate, that is all I would give her.