Caron,
I’m very sorry to hear that you are going through this very painful time right now. You must be feeling very alone but you must believe that you are worth a lot! You have the power of thought and that is all that you need! It is human nature to want to be near the people we love in times of trouble and crisis, like what you are experiencing now with your sickness. That is a healthy urge and necessary urge and so it can be very painful, devastating, and frightening when that need is frustrated – like you are saying has happened with this important person in your life. I am happy to see that you have reached out here. These forums are full of good people who are compassionate and understanding. When I am gripped by feelings of fear or worthlessness I find that the best thing for me to do for myself is to practice metta meditation. This is a form of meditation which cultivates a sense of loving-kindness toward oneself and also towards others. It opens up the heart and allows it to heal as well as pour out your natural ability to care and love yourself and your world. You may not even know that you posses this and can exercise this quality even in the midst of all your suffering.

This is one I found that gives a good overview as well as guides you in the meditation itself.

May you find peace and warmth even in the midst of great suffering,

-J.D.