Hi ladies, I need some advice..

So, my boyfriend has been acting strange recently. He makes me feel below my worth and never missed a chance to let me know that I'm doing things wrong and generally just remind me that he's above me. When things are good they're really good, he's thoughtful and kind and sweet, but when they're bad he's so hurtful that it leaves me crying for days..

We haven't been 'active' for weeks because he hurt his leg playing football (but still can't tell me exactly what team he plays for??) and two nights ago I found him snapchatting another girl. My ex of 4 years cheated on me, and I felt physically sick at the thought of my current boyfriend doing the same. When I asked him about it he said 'I wasn't just snap chatting a girl I was talking to boys from work too' then later told me it was his friends girlfriend. Even though he's given an explanation, I have this horrible gut feeling that's he's lying. His relationship status is hidden on Facebook and his friend jokingly said to him at a party the other night 'you love Ashleigh' and he screwed his face up in disgust.

What would you girls suggest doing? I feel like if I keep casting this up to him he'll go meant but I feel ill with thinking about it...