Should Treatment Be Taken For Narrow Vagina?

I was told by my gyno that i have a narrow vagina...my treatment was masturbation...creams..and a rubber penis to open me up..not sure why i have to do this..please explain..there are times when sex still hurts feels like a cut..there are times when i am ok..had no sex for 9 months..back on track now..just wondering why all the treatments..