Ttc for over three years

My husband and I have been trying for over 3 years we started out just not preventing it and then after 6 months or so I started testing and watching with the app. I asked my OB after a year and a half and she kind of just blew me off. So I have an appointment the 16th to find out what's going on. My question is are there any questions I should ask and what should I expect? I just found out my brother in laws wife is pregnant after 7 months of marriage so she lot pregnant after 6 months it's hard to swallow and I can feel depression coming on. It seems like everyone I know is pregnant but me....I could go on but no one wants to read all that