I'm upset that my bf is texting his ex girlfriend when we are together and possibly lying about it when I confronted him later
Would it help you to find out if your boyfriend is texting his ex?
Yes, I'm worried that my boyfriend would want someone else.
It's not right for him to stay in contact with his ex if it's upsetting you. You should sit down and have a talk with him about it.
It's not my style. I don't want to be the one to tell him what to do or bring it up.
You can improve the communication in your relationship by discussing the concerns you have. By not telling your boyfriend you will only begin building resentment towards him without facts about what he is doing. Talk to him about your concerns so that you know what is going on.