I can't get horny!

Me and my boyfriend have been together for almost two years now, and we have a great connection. In the beginning we used to have sex all the time no problems, no worries, no lube. Then we had a baby and I just didn't want to have sex for awhile I was breastfeeding and I just wasn't in the mood. But now our son is a beautiful 7 months and I'm ready to have sex now, only problem is I can't get horny. I've tried talking to my boyfriend to tell him things that may help but its not working. I won't get wet like at all i've even tried watching porn. It's like I want to have sex with him but my body doesn't can someone help plz.