Advise please

I’m getting married here soon and Iv just been thinking and have always thought “why don’t I have fear of losing him”.. in my past relationships I always had the fear of losing them. But with my fiancé, I have not once feared losing him. Maybe I’m just overthinking, getting in my head, or my anxiety taking over. I talked to him and explained it just like I have here.. he said “you feel safe with me?” “We never go to bed with an on going argument, we wake up the next day and it’s in the past.” “We don’t hold grudges” I just kept shaking my head as he held me. Now that went on but he basically told me i feel so safe and “at home” with him that I have no fear. (He is so genuine to me.. sometimes I feel like I don’t deserve how good he is to me)

I know that’s a lot to read, but I really would appreciate any advise on what anyone of you think. (A little back story, to help you.. I was in a relationship prior to the one I am in now. It was for 5.5 years and I was always scared of losing him. Like we would always fuss, these fusses would drag out for days, and so on. Me and my ex were engaged for 1 year out of the 5.5 years. Then he cheated on me for 8 months... while me being oblivious of it.. I thought I was happy/in love with my ex. Maybe I was or wasn’t, I don’t know. I let my mind get in the way of my feelings. So I never know what I’m truly feeling. Or that’s how I feel. Moral of the story I had fear of losing my ex but I’m not having the fear of losing my fiancé..) and I’m trying to figure out why.. Iv never been so fearless of losing someone I love.. ?? Help me..