Hopeless and worthless

Lately I have been feeling like everything my husband and I have been doing to get pregnant has all been for nothing. We have an appointment on Monday with a specialist but I'm not sure if I want to go. I want to have babies but I'm scared of what the specialist will say. Fertility issues run in my family (one of my aunt's can't have kids) and I only have one period a year. I know others have been through this as well and have had kids that doesn't make anything easier. I feel worthless and can't help but think how selfish I am keeping my husband in a marriage where he may never have children. I know he wants to have kids but if we can't then we can't. I haven't been sleeping well lately because I lie in bed blaming myself for things I can't control until I finally get tired enough to pass out. I can't tell any of my family or friends this because I'm sick of people either telling me it will happen when it happens, I'm still young (I'm 25 but if I only have 1period a year we only have at most 15 more chances to have a baby) and have plenty of time, or worse yet that I'm over reacting. I deal like I needed to share this with someone. We have been trying for 2 years now and like I said at the beginning I don't know if I can do this anymore. I'm scared because I'm broken and no one can seem to figure out how to fix me and I feel alone because everyone my age is either pregnant or has a small child. I just don't know what to do anymore.