Hey man, im 17 and have gone through a similar 'isolated' phase, no friends, the fear, anixety, the exhaustion and depression. It really sucks. But by simply making the decision to change your mindset and stop feeling like this, you're already on your way to achieving your goals! As you already probably know, the older we get, the harder it is to make friends and build meaningful relationships with others. You mention that you still keep in contact with one or two people from high school, that's good and the fact that you've asked to meet someone despite all this is definitely a step in the right direction. The talk therapy is also going to help in a big way too! Just keep focusing on improving your speech no matter how long it takes until you feel confident enough to go out daily and enjoy that social life you've always wanted.