I thought friends are suppose to be there for you

My friend is very close to me and my sister and my sister has been going through stuff and she’s talked to my sister and recently my sister has made poor decisions and my friend he given my sister a lot of advice and me and my friend barley started talking about it and now wants to shut me out because she’s tired of it. Like I only talked to you twice maybe 3 times about it? I feel like my friend should be there for me, if she’s tired of my sister then be tired with her not with me who is also a godmother to my child. And wants space from everybody. but like i said I thought friends are suppose to be there for you I guess not