I understand how difficult it can feel when there are changes like you explain. I know for myself that although it is hard to do, that when I take control and do what I am afraid to do, it always helps me to feel more empowered and in control. It is normal to be wary of change, but combine it with fears from the past and it makes it doubly hard!
It feels you are having to step outside a comfort zone. If you are able to get it sorted, very soon you will get used to it and your comfort zone will be increased in size. Try to believe in yourself and you ability to manage this change - you will be ok.
Moon