Trust Issues.

My boyfriend and I have been together for nearly 2 years now we have a baby that will be here in March, I love him so much but he has done things to cross me in the past messaging other girls inappropriate things, and I've been hurt by it but I forgave him multiple,multiple times. Its probably my own fault but now I find myself being "over protective" I'm not sure if thats even the word for it. I go through his phone all the time and i get upset at just about anything, if he adds another girl to his Snapchat or follows certain girls on Instagram i usually don't start arguments I just block the girls. But I feel like that upsets him. I get upset when he compliments other girls calling them beautiful or whatever. I have crazy trust issues and I hate it I was never like this in the past till he started doing what he did the first year of our relationship. I feel like I can't change I keep telling myself I'm gonna give him space and let him do what he wants and leave his phone alone but I always get like all these thoughts that hes doing something really bad and hate it. How can I fix my trust issues I'm so scared of being hurt by him again but I don't want to lose my relationship. This sounds so toxic i know I'm sorry.