If this is just a new situation I would say just let the dust settle a bit before you make a big decision.
I was in the same situation last year. I had a friend of 20 yrs being my cheif bridesmaid and a friend of 10 years being my bridesmaid and had a falling out with both of them at the same time.
It was during a time that we were finding out that my dad had a secondary cancer which was terminal, and finding out how long he was expected to live. I had done really well until my 2 friends did something to upset me and the floodgates about everything opened and I asked for them to give some space to work through how I was feeling.
They did an interventiona dn told me I needed medicating, shouldnt get married, should spend more time out with them, stop breastfeeding so I could drink, and not think of my family when I was with them and they made a choice not to be my friend anymore.
I let the dust settle and after 10 weeks I asked my 2 SIL's to be my bridesmaids -oh god Im crying now- and they were nice enough to do it for me. They were the same size of my first bridesmaids.
3 weeks after I did that one of the friends-10 yr friendship- came to me and we worked things out, though it will never be the same. I had to tell her that her spot was now taken.
I found it hard because my family in Aussie adn my new bridesmaids were only really there on the day so I had to do most of my planning by myself.
So I really understand where you are coming from and it is sad that this has happened for you because it is really hard to deal with. I say take a few weeks to make your decision, and if you decide to ask someone else then ask your ex friend for the gifts back.
I really hope that this works out to be a happy resolution either way, my one regret during my wedding preps was that I suddenly didnt have my friends there to support me.
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