I'm mad at my fwb
What's wrong with your relationship?
The sex part is over with them. I want to get into another type of relationship
The relationship you're speaking of is quite casual. It may not even be a casual relationship for you anymore, but that is not what you originally agreed to. You should speak with the other person about your desires and get this sorted out properly.
She can't keep up with me and she's not dating material.
It may be best for you to part ways with them if you realize that you were not getting a lot out of this.