When will I be ready?

I’ve been in an on and off relationship for 11 years, she is the love of my life and best friend..or was, but I keep holding on to the past and wish it could be fixed.. I haven’t tried looking for anything because I always just hope things would work out, but it’s getting to the point where I’m telling myself to move on and try to salvage being her best friend. I just want her to be a part of my life still. Basically though, how or when can I be ready to get back into dating?