The 40-year-old actress - who recently realised she is not ready to date following her split from husband of 11 years 'Breaking Dawn: Part 2' actor Peter Facinelli - claims she is desperately concerned about her former 'What I Like About You' co-star who is like a ''little sister'' to her but has so far failed to reach her.
The mother-of-three told 'The Jeff Probst Show': ''I haven't talked to her. I've tried. She's like a little sister to me, so I would love to wrap my arms around her right now. But I haven't been able to reach her.''
Amanda, 26, has suffered a string of setbacks recently including being charged with driving on a suspended licence and having her car impounded.
She was also involved in two bizarre episodes in September, locking herself in a store changing room for nearly two hours and refusing to come out and stripping off during a gym class and friends say her parents don't know what to do as Amanda has cut contact with everyone.
The troubled starlet recently dismissed reports she is spiralling out of control and proclaimed she is simply a retired young millionaire.
Jennie admitted that like Amanda she too thought her career was over after the end of their comedy series until she realised she loves being an actress.
She said: ''I forgot that I actually like what I do. I thought that I was done as an actress [after the sitcom]. I really thought that I was retiring and I didn't want to do it anymore. And now I'm doing it again, and I really enjoy it.''