Sex Hurts

Whenever I have sex or have ANYTHING inserted into my vagina other than a tampon, it feels like I'm shoving a FUCKING CACTUS INTO MY STOMACH. My fiance and I are both frustrated by it and I know he's understanding and will love me anyway, but I really want to have enjoyable sex with him. I know it's not because he's too big (probably is tho lmao) because EVERYTHING I've tried hurts. Fingers, toys, etc. I don't know what to do, please help me I am die