Is it legal to let my friend die.

I have an ex girlfriend who I am still a close friend of. I don't want this to sound like I am encouraging her in anyway. She is in the process of ending her life. <br><br>She is suffering from a type of brain cancer. We live in the uk and the treatment for her is chemotherapy and radiotherapy. The cancer is located in an area of the brain which is controlling her motor skills. She has had two treatments of chemotherapy, which has left her blind in one eye and paralyzed from the waist down. <br><br>Her two choices are treatment or death. She has chosen death. <br><br>She is not in any pain and other than paralysis and blindness she is comfortable. She has now decided to end her life. By stopping eating and drinking and also not taking her medication for her cancer. She is in no pain and so far seems a lot better mentally. <br><br>I don't want to feel responsible for her death. I don't think that's fair on me. <br><br>I understand that she wants to end her life. I would probably do the same if I was her. I want to be there for her until the end. <br><br>I have spent the last 48 hours with her and she is comfortable. I am worried that this is the start of something which leads to a police investigation.