I've had a couple of students that are the exact same way. I tell them that as long as you are trying to learn on every solo you do, you'll probably learn far more than you could with an instructor. Maybe not new material, but the stuff that you already know will definitely get stronger. My brother is going for his commercial rating and is almost done. He's pretty hesitant about the night flying requirements, so what I did was go up on a night flight with him and pretty much just observed him. He did great. Maybe because I was there but either way I didn't touch the controls once. You've already got your PPL and almost your IFR but there's nothing that says your solo nerves instantly go away with your certificates. I guess it is what it is, just buck up and go out there and solo. Hit the traffic pattern and practice power off landings. Step it up to a cross country here and there. Before you know it, something just clicks and the nerves get replaced by the confidence your experience will bring.