I’ve been with my boyfriend for three years, but I still struggle to trust him. He cheated on me in the past, and although he’s apologized and promised to change, I find it hard to shake off the feeling that he’ll hurt me again. I always feel insecure whenever he is using his phone and smiling and laughing. Due to this I am always checking his phone to see if he is cheating on me. I want to stop this habit and trust him, but I don’t know how to. What do I do? How can I learn to trust my boyfriend again after he cheated on me?