Losing erection with condom

I like to think im a considerate lover, and i can even say that prefer foreplay to actual sex, and i put alot of efansis on trying to have foreplay. The problem lies that i lose erection while having sex, i dont feel much during sex with a condom on and it afects my overall mindset if i do lose it, i know its natural that it happens but it crushes me deeply although i try to act like it doesnt. I dont have much expirience with out a condom as those were risky tries but i cut it short cause it feels like i will cum really soon and i dont get to cum cause of fear alone. When i do manage to cum with a condom on it often is in a cowgirl position where i do the really quick movement ( you guys know the one). For those that will say its a masturbation thing, although i do masturbate every day its cause im not getting any, it lasts about 10 to 15 min dry, if i use lube i varies from real quick to 45 min and i sometimes can go again almost immidiatly after unlike by going dry.