An advice to KJO484 (Regret,Love).
I'm just a stranger here, but if in your case, I'm probably the "you" you mentioned. Let's me give u this small advice, Leave him/her alone if you still dont know what to do with your feeling toward them. You mention your regret losing them and that you still love him/her, my dear, this is too late. If you knew their worth earlier, thing wouldn't be this way. I am not blaming you or anything but I'm pretty sure him/her is in a good place right now. If you still "dont know what to do", dear, do him/her a favor and not interrupt their peace. Your uncertainty will only bring the worst. If one day in the future, your heart remain the same and they too, universe will pull you together. Who know.