I’m heartbroken and tired...

I’m so sorry i just need to vent... I’m so tired... I have been having a very light period for 5 days now so light I only wear a panty liner... My boobs are still sore, they always stop hurting a day before AF arrives, I’m currently 16dpo and BFN!! I feel completely gutted, I feel angry, I feel sad.. why is TTC so hard? Why is Mother Nature so cruel? Am I not good enough to be a mother? I’ve been TTC for 3 years.... with 1 chemical.. I pray so hard to one day be able to experience that BFP again. I’m so heartbroken!! I can’t help and cry at the fact I cannot experience something so beautiful.. while everyone around me is getting pregnant... my sister just announced her 4th pregnancy and I don’t even know how to feel.... she’s not fit to be a mother, she’s immature and already lost 2 of her kids to her ex boyfriend because of it. I don’t know how much more I could take..... 😢😢