Sex drive

I have a horrible sex drive. One week I want almost every day and then for 2-3 other weeks it’s like I feel I could go in life with no sex forever. So my fiancé struggles and I try to talk to him about it and honestly do give it to him even on the weeks I don’t feel like it it’s just maybe 2 or 3 days at the most though... but apparently that’s not enough and it’s causing problems for us... ever since I had our son I just don’t know it changed for me I guess. Last night he became upset with me because I wasn’t in the “mood” and today he’s barely spoken to me. I tried coming to bed with him because I feel so guilty over this and bad that he won’t pay me mind because of this and all he said was goodnight and went to sleep. What should I do ladies?!