How far is heaven?

I've been struggling through two ideas, heaven and selfishness, that are really intertwined for me, and I haven't really come to a conclusion that satisfies me. I'm not even really sure how to organize all my thoughts into coherent statements. Basically, I'm tired of hearing about becoming a Christian so you get out of Hell. I hear "It's not about religion, it's about the relationship," and then two seconds later "and you get out of Hell." People talk about being selfless as a Christian, but being Christian is selfish. ¹⁹"Do not store up for yourselves treasures on earth, ... ²⁰But store up for yourselves treasures in heaven..." How is that not selfish? Would people love Christ if going to Heaven when we die wasn't part of the deal?

I think the big issue is that I'm selfish. I've got selfish motivations. I really want to be selfless, but I don't feel like I'm being selfless. I don't feel selfless storing up treasures in Heaven. I even feel selfish accepting love and peace and other blessings from God. I just feel like it's so much about me, what I want, and what God can give me.