Need Support

Anyone else experiencing extreme low self esteem during their 3rd trimester. In my previous relationship of three years I was cheated on the entire time and I went completely crazy and insecure towards the end. Now in my current relationship with my LOs father I’m feeling fearful something similar will happen. Now back track he is an amazing man and honestly my thoughts are completely irrational. He has been nothing but supportive and loving. But it’s like any little thing makes me feel like I don’t deserve him or I’ll push him away with my craziness. I know he’s faithful I just don’t know how to get this stupid bug off me. This is the happiest I’ve ever been and the last few days I’ve been struggling with myself. Any help is appreciated.