I am sorry that you are feeling discouraged.
I bet that you are not far from feeling the difference. When I first started, my doctor told me that losing just 20 pounds would make my knees feel better but it didn't. I was around 250 before I felt any difference.
You are working on your Master's so you are an educated person. Think about when you got your Bachelor's degree. During your freshman year, did you dwell on having to go to college for 4 years? I bet you did not but instead took it one semester at a time. Weight loss is very similar. Don't dwell on the amount of time that it will take to loss weight. Break it down into small manageable goals and focus on that. Maybe start with 10 or 5 pound goals.
You have been successful in other things and you can be successful with weight loss also. You can do this!