Idk what to do anymore

So last school dance me and my bf went to we got into a fight and he ended up taking a picture with another girl and to the same type of picture with me and he tried to hide it and I found out from someone else and recently he got Instagram and he messaged her wyd and I told him how it made me feel that I saw it on his account and this was his response....

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Idk what to do anymore I told him how I felt and he doesn’t care how I feel what should I do now oh and btw the dance was almost 4 months ago