Regaining confidence after abuse

Ericah

I was mentally/emotionally abused when I was 15 and I’m 19 this year. I was abused, raped, and sexually assaulted that whole relationship. We were together almost a year. So when I was about to turn 16. I’ve been with my fiancé since September of 2017 and it’s still hard to FULLY trust and get confidence back. I’m insecure as shit even though he reassures me everyday. Reassures me he’d never cheat and stuff like that. He’s never given me a reason not to trust him. Last night I told him I was thinking about going to therapy, but does anyone have suggestions on what I could to before therapy? Like little exercises to help me get better?