I do not have a womb and my husband has no clue

I am 31 and have been married for four years. We have been trying to have a baby for a long time but I know that I cannot have a child. I don't have a uterus as it was surgically removed for reasons I cannot explain in public. Now he is pushing for us to go to a fertility clinic so we can both be examined. I have known this all along and I am afraid that if he finds out he is going to leave me. I am totally confused and scared as I don't want to be alone in this life. Please advise me.
{Lydia}