If you refer to someone as atower of strength, you appreciate them because they give you a lot of help, support, and encouragement when you have problems or are in a difficult situation.
[approval]
Pat was a tower of strength to our whole family.
See full dictionary entry for tower
tower of strength in British English
a person who gives support, comfort, etc
See full dictionary entry for tower
Examples of 'tower of strength' in a sentence
tower of strength
She really has been a tower of strength through all of this.