tips:
i am the same way your not alone. i dont like to even go out in the car alone or go to a store alone.lol it would help if you had a friend or a child of yours to ride along with you someone you can trust of cores.
try geting out more maybe check out some support groups or get into some kind of hobby or something you love to do. things like that will pass the time away fast and keep your mind off of the fear of being alone.
perhaps volunteer at a school to read to small kids.
check out the library they have things going on there usely if there any thing like my library. take walks in the woods visit your friends.
i know it is so hard its a fear i have i dont think ill ever over come it my self.
these are a few ideas that i have. just trying to help. sharing a few things my therapist had suggested to me .