Im so scared to come out

I've been wanting to "come out the closet" to my mom. Ik she knows im not straight since shes told a family member "I wouldnt be surprised if the introduced me to her girlfriend". Thats nice to know she'd still love and support me if I was les. My problem is that im bi (obviously), AND FOR SOME REASON, SHE HAS A PROBLEM WITH BI PEOPLE 😭😭. Help?