Too thin?

Hey guys, I'm looking for some opinions. I've struggled with my weight for over a decade due to pcos and hypothyroidism. Since my son was born September 2016, I've lost 80 lbs. I was 215 at conception, 230 at delivery and am now down to 150 and in a size 6. I'm very proud of my progress, but I have what my husband calls "fat goggles." When I look in the mirror, I still see an overweight person because I was heavy for so long, even thojfg logically I know I'm not big. My goal weight to begin with was 135 lbs, so I'm not that far off, but I've been told if I lose anymore, I'll look sick. My in laws have already made comments that I'm getting "too thin." I'm 5'7" so I don't think 150 is too small. So my question is, do you think my goal weight is unreasonable? Am I going to look sick or would another 15 lbs be fine? I'm honestly not trying to fish for compliments or anything, I just feel like I can't trust my own eyes right now.