Life has a way of working it's self out the way it's supposed to. The thought of change is always frightening. The thing is you're going to have to do what feels right for you. Like you've said to many other people here there isn't any hurry. I'm pretty sure I'm not just speaking for myself here I want to see you happy. If it's going to increase your happiness to include your new friend as a partner then that's what you should do. We regret things we chose not to do far more than things that we chose to do most of the time. Fears are normal and being able to put what you're afraid of out there means that you're going to be able to get the reassurance that you need.
Everything will be ok in the end. If it's not ok it's not the end.