How awful am I?

So my boyfriend and I have been together for 3 years next month. He has an older brother that has been in the most UNSTABLE relationship for a little over a year now. Well my boyfriend and I have been talking about getting married and about how I want to have a baby. My boyfriend said we just aren’t financially ready for a baby just yet (and I can’t say that he’s wrong), but I definitely have baby fever. Of course a week after I tell him I’m ready for a baby, his brother tells us that his “girlfriend” is pregnant! I’ve never felt more sick to my stomach and more jealous in my life. I feel AWFUL for feeling this way, but I can’t help it! I just feel like they don’t deserve to bring a child into this world with the way their relationship is ( and frankly they just aren’t stable in their lives, she still lives at home while his brother literally just had to move in with us) and it’s so not fair! I know I’m terrible for feeling this way! But why him and not us??!! It’s so frustrating!!