Just want to let it out

So I found out I was pregnant in early February and I was really excited. I had a chemical pregnancy in November, so I wasnt expecting anything so soon. My sister-in-law had just announced that she was 7 or 8 weeks pregnant when I was waiting to test. We also hadn't even really tried to get pregnant except for on 2 days in the entire month, so I was extra surprised. I got on prenatals the day I found out and scheduled a confirmation appointment with my doctor. A week after I found out(I was 6.5 weeks by then, my period was 20 days late, and I was having every symptom, although my symptoms were mild and mostly faded away so long as I took my vitamins) the doctor did a urine test which came up negative. She thought it was strange, and told me that based on the test I had taken at home, my symptoms, and my extremely late period that I was pregnant, but that I probably wasn't producing very much hormone because I am very small. She also said there was a possibility that I had ovulated a week later than I thought, so she decided to run a blood test. It came back negative, and she told me to expect a miscarriage, but that if I didn't bleed in the next week that I should come back and they could either do another blood test or a transvaginal ultrasound. 5 days later, my back started hurting insanely bad, and I started getting cramps. I was in as much pain as my periods, except that the pain was all in my back as opposed to my stomach area. I started bleeding whenever I was active. If I stood up, I would be fine, but if I took a single step, or if I moved my arms, I would start bleeding very heavy. I passed a lot of tissue, and a lot of clots. I called the doctor, and she confirmed that it was a miscarriage. This week,my sister-in-law finally made her very first appointment. She hasn't been taking any vitamins, she has been dehydrated and isn't eating, when she does eat she throws up blood. She is 14 weeks along and only went to the doctor because she wanted to know if throwing up blood was bad. Today we had a family get together, and everything was going well. I forgot my husband had told his mom and the rest of his family when I fell pregnant. Before one of his aunts left, she said "Congratulations on your baby!" And rubbed her tummy. I broke down in tears and we had to leave 5 hours early because I was inconsolable. It's so frustrating that I wanted that baby, and I've been taking care of myself as best I can, and I lost it. It's especially frustrating because my sister-in-law is practically killing herself because she's starving and dehydrated, and doesn't want to take care of herself, and her baby is perfectly healthy. I've been trying so hard not to have bad feelings toward her for it, but it's just killing me because it makes me feel like I lost mine because I'm so small, and my bmi is very low. (17.5) I just can't stop crying. I wanted it so bad. My husband has been trying to tell me that he will get me pregnant again and that he has a good feeling about tonight and that I smell different (and I'm supposed to ovulate today) but I feel like he is just trying to get me to stop crying. This really sucks.