Should I end my relationship with my longtime ?

I have known my friend for over 29 years. She has been there through thick and thin. We have always kept in touch by email, phone, or text. A few years my friend stopped responding to any forms of communication. I tried for a period of time, then stopped and took her contact info out of my phone. Approximately a year later I was driving down a very busy road in a city.. when all I receive a text message from a number that I did not recognize. The message said “ I have received all of your messages and I am very proud of you.” I pulled over and called the back. It was from my friend. The call went to voicemail. When I finally got to speak to three months later, she said her husband had passed away. I told her not do this again. I tried reaching out to her children on FB, I did not get a response. I thought she had passed away. Over the last few years she has been “hot and cold” with me. She says “She said she sees my texts and emails, but does not respond return the messages.” My friend told she would do that né again, however she didI am very confused and conflicted about what do in this situation. Why is she doing this and what should I address the issue??Any advice would be helpful.