Please help, I'm an ESL student but I am scared to speak with American.?

I am an ESL student, currently studying in America. I have been here for two years. I go back and forth between Thailand and American during summer. When I came back to America, I had a confident conversing with American for only one day( the day that I arrived), but its all fade out. The anxiety and insecurity of not being understandable and not fully grasping a conversation frighten me. I have been crying for almost everyday in the first year and struggling to stay here. My parent devotion to my education has given me a strength to be here but deep down in my heart I suffered. I know my situation and hired an ESL tutor which greatly helps my pronunciation and accent. Even though, having an ESL lesson (conversation)almost everyday is a good thing, I'm lacking the real american culture experience and speaking which someone who are not ESL instructor. I started to mumble whenever I speak with American stranger. What should i do to increase confident and making American friend?