And lost my virginity with him

He had a gf of 1 month, when he told me that he liked me. Because of that I believed that he was going to break up with his gf for me. But he never did. And I am feeling so devastated, because I got so deeply in love with him and now I am planning to quit my job. Because I can not stand to see him every time at work. I really expected too much from him, but he never did. He just told me that I was the love of his life, but that he could not hurt his gf's feelings. 

My heart is very broken

I can not trust him, because he hurt me and it feels like he just used me for sex

And I am writing this to let myself feel some relief.