just feeling defeated

Meg • TTC after losing our baby girl at 37 weeks 👼🏻
I guess I could just use some words of encouragement or success stories or something. I'm just feeling so alone and defeated. 
This month I was on 100mg Clomid (my 4th cycle). I was supposed to get an hcg trigger shot, but dr said my cm looked great and just to have sex as much as possible for the next three days. 
Went in for my cd21 progesterone level and found out today that it was only 7.6. 😔 nurse thinks I may have a progesterone issue and now I'm scheduled for another appt tomorrow. 
I'm just so frustrated because I never had issues getting pregnant with my first three just needed help staying pregnant and took progesterone supplements. I told my new dr this and he just kept insisting that Clomid will raise my progesterone level enough and I don't need the supplements. We've been trying for 2 years now and now my husband is leaving to go to school in August which means we have to wait another 4 moths to try again. I'm at work right now (on a break) and just want to cry. 
Oh and also...my sister in law (she hates kids) just told us she's pregnant last night and my husband insensitivity says I'm so excited for them...I guess we better work on making a baby ourselves huh. 😞