First off - no - this guy was not acting right, or treating you right. Dont get me wrong, guys can have friends, but staying out all night on her sofa...WHAT? That is not normal. His behavior (texting her all night), is enough to cause insecurities and doubts. I have male friends. I don't text them all night. There is a line. Trust your gut. In this instance I think you are spot on not to trust this guy. Sometimes you just know.
You do need trust - but your partner needs to treat you right and with respect. This guy, isn't treating you right, or you wouldn't be hurting.
My mother told me, and this hit me hard - a guy who loves you - will never put you in a position to lose you. Staying out on a girls 'sofa', and texting her all night? Isn't putting you into a position to keep you.
The mere fact you're questioning this relationship says it all. This isn't deep love. He doesn't know if he will be with you long term. Girl get out. You're going to regret staying with him because this guy, is already uninvested. Get someone who knows your worth - and will treat you right.