Only follows girls on Instagram

How would you feel if your s.o only followed girls on Instagram and lying to you about adding girls on snapchat saying “They follow me first. They add me on snapchat not me.” Always checking other girls stories on ig and sc. lying about their friendship or whatever “we’re just friends” when we first started dating he would always flirt with other girls and I asked him about it and lied about “not talking to other girls or not flirting with them. That they’re the ones who starts the convo” I know these girls irl and I find it so embarrassing. Being seen with him in public and him staring at them the whole time. These girls act so rude to me smh idk what to do anymore tbh..