My (28M) girlfriend (29F) has gained a lot of weight and I don't find her attractive anymore. How should I approach this? She is refusing to make any changes.

My girlfriend and I have been together for five years. She's always looked after her body, going to the gym, running and cooking. She has always looked after herself. I have always found her incredibly attractive and in great shape.<br><br>In the last year and a half, she has completely stopped taking care of herself. She's gained around 50 pounds and taken to just eating fast food, processed and sugary foods constantly. She has completely stopped being physically active. I have tried talking to her about my concerns on many, many occasions. I have approached the topic gently and suggested getting back into the things she used to enjoy. She just says that she was "bored" with it, or doesn't have time and that I should leave it alone. It is getting to the point where I just don't find her attractive anymore. She is turning into someone completely different. I miss my girlfriend. I am at a complete loss, I don't know how to approach this anymore. She is refusing to compromise and told me that she is going to be this size from now on. I don't know what to do, I have begged and pleaded that she gets help. How do I approach this situation? Can anyone please help?<br><br>TLDR: My girlfriend of five years has gained around 50 pounds in the last eighteen months by completely abandoning her healthy routine. She has refused to make any changes when I have approached the topic gently. What should I do?