Family member needs help

My older sisiter has been having some issues for about three years now. Almost 3 years ago she suddenly quit her job. Being so busy with our own lives we did not even notice she had stopped working. An acquaintance mentioned this to my husband. We asked her and she was very angry and did not say much other than the fact that she was infact not working.
Time went by and she started acting weird, she donated a very expensive phone she had recently purchased. She donated expensive clothes and shoes she bought. She stopped talking to a lot of people and basically stopped caring about life. The one friend she talked to at the time told me that my sister felt like no one cared for her and she did not want to go on.
Unfonrtunatelly my life at the time was very busy and when I had the time to talk to her and ask her what was going on she would react very angry. I was pregnant at the time and gave birth to a beatiful daughter in January 05. I was really busy with my own life, my son and my baby, husband, work and hardly had time to spend with her. All this time my mother has been trying to help my sister but she is too getting tired. She went to the doctor about three years ago and was told she "probably" was depressed since she slept a lot and did nothing else. She refused to get treatment at that time. Recelty she went to the same doctor and was told that if she had taken the treatment back then she might be fine by now. She took offense and claimed to have stomach pains and blood in her stool. The doctor said it could be an ulcer since she had stopped eating. The doctor ordered her some tests and prescribed medication. Without insurance the only thing she did is buy the medication for her stomach and the depression. The tests were not performed becasue without insurance it is very expensive to get the tests done. We have asked her to apply for medicaid but she refuses to do it. Since she has been without a job for such a long time her savings have just about depleted. All this time she has been living off the savings she had set aside to buy a house. Now it seems like all her dreams a gone. There is a much younger guy ( 6 years younger) who is interested in her but might also loose interest.
What can we do to help her get back into life? Please help!!!

Tell her that you are there for her. make sure she knows you care, and that she cant come to you for help. she might not ask for any or she might get mad but if she knows that you care and want to help she might feel better and will want to talk to about it more then if she didnt.
ofer her a place to live like your house or something like that, so she can get back on her feet easier.
i hope everything turns out well