The Happy Days actress, who is said to have died from Stage 4 cancer, worked with personal trainer Michael Banyar some years before she died, and he tried in vain to help her get in shape and prevent her from falling off the wagon.
"There was always this kind of urgency that this was her last ditch effort to make it in acting," he told RadarOnline.com. "After Happy Days and everything else, her career plummeted — we talked about it a few times."
"She wanted to get back on track and be ready physically, mentally and emotionally before it was too late," Banyar added. "Erin was taking it one step at a time, but she would have taken any job she could to be employed again. She'd always say, 'I'm too darn fat, don't take any pictures of me until I'm in shape' and she worked really hard."
Michael says he was aware of her drinking issues and worked with her on a healthy living plan, but insists he saw no sign of drug abuse.
The pair trained together three times a week for three months for a series of Celebrity Fit Club on VH-1.
"She would come to my private studio a lot and I got to know her as a client and a friend," Michael said. "We kept in contact and I sent her Christmas cards, but after a while they started coming back, 'no address found.'"
"I heard she was living in a trailer trying to write her memoirs and I sent letters but never heard anything. Her phone was also disconnected.
"She was weak but she was always really positive and made a lot of progress when we worked together. I wish I had more time with her.
"I knew there were problems in her life, with liquids, let's say it that way, but I just know she was trying really hard to change her lifestyle."
Erin, 56, died in a mobile home she shared with her husband, Steve Fleischmann, and mother-in-law Donna Woods, on April 22 after reportedly being diagnosed with cancer late last year.
It was believed to be Steve who made the 911 call this weekend and she was found dead on arrival at the trailer park property in New Salisbury, Indiana.
"Steve is shy, but there was a really good connection between them," Michael added. "She had a lot of support from him, he's a good guy. Whatever pain she was suffering, I know she is in a better place now.
"My heart goes out to Steve and her family and friends and I hope they all find peace."
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