I don’t know what to say. Really sad and the chances are high that they have stolen your idea. It’s hard to do anything legally and there would be cost implications too.
I would just say don’t lose hope, you are never defeated untill you accept defeat.

My personal feeling is continue with your current job and continue applying. As you say, you can easily get a job of 80K-100K if need be so continue getting 150K till the decides to close or ask you to leave. Do not forget to continue saving.