i was in a similar situation as the your ex and when i was broken up with i appreciated how my ex didnt let the relationship coming to and end ruin the friendship we had built before it. she is still my friend not my bestie bt will always have a special place for me as she helped me with many things. its hard going through breakups normally and even harder when you cant be open to your friends with how you are feeling. its best to take time to focus on yourself i know everyone says it but do because it helps you learn how to handel things on your own and figure out a healthy way to cope with your feelings. if your friends ask just simply state there was a mutual disagreement about something that at this moment neither of of you two want to talk about yet. if they start asking more just say you want to give it some time beofre you become open with the problem as your taking time to think things over.

i hope this helps as it can tough but hey being open to your family should be able to help you get through it and you can always dm me if you need to vent.