Infertility Clinic vs OB

I did 2 rounds of Letrozole at 2.5mg and my OB referred me to a infertility clinic. Appt on the 10th. My concern is obviously the cost of infertility treatments but, I'm also confused as to why he basically just gave up on me after only 2 rounds of the lowest dose in Letrozole. Do I call around to different OBs? Give the infertility clinic a try and look at costs? I feel so defeated right now. People literally suck. Anybody with experience or advice would be so much appreciated!