Just the fact that you have periods of fluency should tell you that you are capable of greater fluency. Most everyone is. Too many of us believe greater fluency isn't attainable. Despite the fact that our fluency has highs and lows. It's about perseverance. Continue seeking fluency. I'm a huge advocate for speech therapy. I hear about a lot of ineffective speech therapy. But there are effective programs out there as well. I didn't achieve fluency until my mid 20s. Honestly, if I had gotten off of my ass and taken my therapy more seriously in my teens, who knows...