boyfriend calls me another girls name

Uhmm... I'm very upset over this. My boyfriend & I went on a date and he ended up calling me another girls name. He said," they're almost the same," when our names are no close to being similar. He always tells me he hates and he's disgusted by her and every time I'm around her she flirts with my man when her man is right there. He says I shouldn't be mad but I'm absolutely furious. I have no clue what to do