I feel like my fiancé has ghosted me after six years together. [55F] [55M]

I'm the 55-year-old woman, by the way. We had a disagreement just before Valentine's Day, but we resolved it. On February 15, I received a random Instagram message from a provocative model saying negative things, which made me upset. I confronted him about it. Just to clarify, I live in the U.S., and he’s in Australia. I'm planning to immigrate in four months. Right after I confronted him, he cut off all communication. I'm not blocked, but it seems like I've been muted. To make matters worse, I was hacked. All my accounts were compromised, and I lost access to my chats with everyone I’ve ever messaged. Even messages to my son wouldn't go through. It took me two weeks to regain access to my information, and everything has been changed and secured now. Now, I can't reach out to him to work things out. I've sold everything here, and my house is under contract. I really need to know what's happening, but I'm at a loss about what to do. His mom and best friend have actually blocked me as well. I have only ten Facebook friends, and four of them are deceased. I'm feeling very isolated and overwhelmed. I have a serious health issue, which is worsening because of all this stress. Most of my belongings have already been shipped and are waiting for me. Does anyone know how to contact someone who has muted you? I can't find any death notices. I had the police do a welfare check on him, but he either won't answer the door or isn't home. We've been together for six years and engaged for nearly two years. Any constructive advice would be greatly appreciated.