Girlfriend [22f] flirts with others in front of me. She has a history of cheating

I’m 28M. We’ve been together for 5 months. Recently we went out and she spotted a hot guy at the bar. She has never been so keen to get the drinks. I didn’t pay for a single beer that night.

They chatted, laughed – she was very flirty – and he gave her the drinks half price. I was ignored by both of them. I thanked him but no eye contact and she said nothing to me either.

Later we were dancing, got pretty drunk and ended up kissing heavily against the wall of the place. It was hot but she definitely kept looking over at the guy at the bar in between kissing – it hurt me but I didn’t let her know.

There have been other times – harmless, nothing ever goes further than flirting and chatting, but it bothers me because of something she said: she cheated on a previous boyfriend, kissing a mutual friend in a club when they were there together. This started a new relationship.

The jealousy and feelings of inadequacy really hurt. It makes me think I should end the relationship now, before she does something – even though as far as I’m aware she has been loyal to me. Should I talk to her about my fears or is this the wrong thing to do?