The purpose of a social worker is to make living easier for people and families that need the help. So, if your mom has been talking to a social worker she's taking the right steps.
As far as her needing a psychologist, this is something that you need to address with her first. You cannot have her committed just because she takes an hour long walk and mumbles at home when she gets bored-- she isn't posing a risk to herself or others but I can see how it can be concerning if this is new and erratic behavior.
Talk to her about possibly soliciting the help of a professional and see where it goes from there.