Tired of getting my hopes up

My boyfriend & I have been TTC with our rainbow baby since August 2016.. I had a miscarriage in july 2016... & we've been trying since.. at first it was no biggie when AF arrived.. but lately.. I just cry everytime I get AF... my boyfriend told me not to worry, it will happen when it happens.. but I can't help but get excited about every "symptom" I have. I feel like giving up.. makes me down.. like I will never be able to carry a child again.... I want another chance at becoming a mother so badly 😢