As long as religion doesn't get in the way of your friendship, I would say to still cherish her in your life. Find a way to build bridges instead of closing doors.

Friendships especially one of long duration are valuable

I have friends of all different faiths. If you stopped being friends with her just because of her faith then you were never really friends. Now if she starts acting differently or doing negative things Towards or to you then I can understand ending the friendship.

You have chosen your path; she has chosen hers. As long as she doesn't try to convert you, it should be okay. Unfortunately, many newbies to a religion/sect become zealots. I hope she doesn't do so.

Friends or not I would lose a lot of respect for them, but that’s just me.

I'd say you're friends first and your religion is just one aspect of who you are. I have a great friend who's a Jehovah's Witness, we've been mates since she was about 8 and we can still have a good laugh about life regardless.

As long as believers do not try to cram their religion down my throat, I'm good with it. I have really close friends of all faiths, my best friend for over 45+ years is Catholic, he respects my opinion and I respect his.

I think old friends are rare and you now know that accommodations have to be made probably by both of you so basically I am wishing you both well and hoping that the bits you agree on still are enough to keep you in touch with each other.

Of course, true friends support one another in their decisions. However, knowing what I know about Islam, your friend may very well fall away from you. Islam is very prejudiced against women and your freedoms as a ''western'' woman may become difficult for her to see. She might resent you for them. Good luck!