Why do people change when there's a crowd?

When me and my husband are alone he's all loving and cute and say come here babe but when we are around peoe he acts different. For example tonite I invited my sis and husband over and me and my sister husband where playing FIFA I won and my husband goes u lost especially to a women like this he always try's to put me down but my brother I law said what's wrong with a women like her all confused and alittle annoyed that made me feel bad so the next game I played bad cause I kept thinking of that comment he made and my brother I law goes to him u put her down that's y she's not playing good he gets all nervous and says I was just playing but he always that infront of people real me. Put there women up and make them feel good infront of people but he always does the opposite. I do so much for him cook clean laundry I even wake up at 5am to make his lunch before work and he treats me like nothing I dont get y but it's ok I guess cause he looks like an idiot in the end not me.