Ready to give up

For selfish reasons. I've been exclusively breastfeeding for 6 weeks, I'm a ftm to a hungry little boy lol I've survived cracked nips and surviving all the cluster feeding. The thing is, 2 of my friends just also had babies and bottle feed formula. They are losing weight and able to do so much more and I'm jealous. I normally can't get anything done! I'm so tired of being fat and want to workout and take in more caffeine because I'm so tired. That's selfish I know please don't be mean. But, I'm sad to say I'm so depressed about my weight I'm ready to give up nursing my baby. The first time my so and I had sex we got pregnant I'm afraid he's going to leave be since I'm so much bigger now.