Overweight ambitions

Ms. Velociraptor • 💓💙💙💓💙
My significant other is very overweight to the point that he has blood pressure issues amongst other things. We've talked about losing weight together (as I'm pretty chunky myself) but I'm not sure he is really willing to go through with it. He talks aften about how sick he is of being fat and gross but he lacks ambition to do any physical work. He'd much rather just go through a drive through than go in to a grocery store, buy and prepare meals. 
We just talked about the movie Wall-E and I got instantly heartbroken over the text he sent me.
I think he maybe hurt from the message I sent back to him about staying on Earth. He hasn't replied.
I don't know if I can handle him not wanting to/lacking motivation lose weight. We've talked about marriage and having a family but I don't want a family with someone who will not help out or want to play with the kid(s) in the yard or at the park.
His weight is so bad that I'm not sure if we could even have children. His weight is causing ED and even if he does get it up, there is barely any penetration at all. 
I'm at a loss. I love him tons and he is the sweetest, kindest guy I've dated but I have fears that we don't share the same goals.
I'm not sure how to address this or if I'm just being selfish. Any advice will be greatly appreciated.