It sure is hard... especially if you are scrutinizing your length constantly. A watched pot never boils.
One thing that really helped me was wearing braids. When you have your hair in braids, you can really see the new growth that you are getting. It's also easier to do DC treatments and such, because you don't have to worry about detangling, drying and styling. If you want to keep frizziness from taking hold, you can dry your hair with a scarf tied on, or one of those mesh wrap caps.
Then, when you take your hair down, you really see the growth, instead of feeling like your hair isn't growing.
Are you taking any supplements? I think some girls go crazy with putting extreme things on thier scalp, when taking a prenatal vitamin, a B-50 and a biotin could really make thier growth take off. Not speaking about any one person here, just saying in general I'd rather take vitamins than smear coochie cream on my scalp.