TTC help.

Husband and I have been TTC for 4 years. I was told I have PCOS in 2014. Been on 8 rounds of clomid, I've tried preseed, been to a fertility specialist for a consult, had an HSG last week which was normal, been on metformin, semen analysis was perfect. Because I ovulated on clomid my doctor wouldn't let me try Femara... I am relieved they can't find anything wrong, But I'm also frustrated that we don't know why it hasn't happened. This would be our last month of trying before next year because he's going to be deployed from October to April. Any advice, encouragement, personal experience you've had that have helped would be greatly appreciated.