Ruby hill what a horrible situation you find yourself in,being in a relationship with someone who is not sure of there commitment to you ,that would be very hard to cope with on itself, without your major reoccurring health concerns.As you know without sleep the body and mind does not function well, depression can set in with any diagnosis or treatment of cancer,and also the extra stresses you are under.
Have you had a chat to your GP about seeking professional help with both matters,or are you already seeing someone,it can help to talk with a professional who may be able to offer you an alternative way of dealing with what is happening in your life,or is there someone you can talk with,I found it beneficial in the early days of my diagnosis to chat with a psychologist.
If you are unsure of your living arrangements you need a back up plan.
Have a chat to your specialist about your treatment options and affordability.
Best wishes to you