Can someone with amblyopia ever be free of glasses?

Yes. After the amblyogenic period - maybe age 8-9 years therapy with glasses isn't really necessary anymore. There is no problem with the use of contact lenses as long as one recognizes the increased risk in an essentially monocular patient (severe amblyopia). Also the use of safety glasses should be discussed in depth.
Ambly. Sometimes a person may be amblyopic in childhood, and may be successfully treated. A few of these folks may not need glasses later in life.