In my opinion, it talks about a person who has been in a relationship, probably a long one and he feels bored/trapped or simply thinks that his feelings towards an old partner have burnt out. On the other hand, he has met someone new and they have experienced some great moments together (heaven). Unfortunately, the narrator was still in an old relationship which he hadn't enough courage (?) to end up or was still hesitating at that moment whether he wants to stay with the old partner (and old life). So, the narrator was unfaithful to someone and to a certain point he is aware of his actions. That's why he calls it hell. He knows he has done something terrible, but he couldn't help himself. When he opened new door (love affair, new love), he probably closed the old one (old relationship). He hasn't done it the right way, but when you decide to cheat on someone, you don't think about the consequences so much, it's just a moment, you just want to seize the day.
All those hostilities are probably factors from his old life like e.g. friends/family who try to convince him to come to his senses, his old partner left behind or new factors who appear when he decides to start a new relationship (the impossibility of being together because of long distance that divides them, their old careers, work commitments).
A moral: don't cheat. Ever! And don't let you Id take control over your mind and body.
In my opinion, it talks about a person who has been in a relationship, probably a long one and he feels bored/trapped or simply thinks that his feelings towards an old partner have burnt out. On the other hand, he has met someone new and they have experienced some great moments together (heaven). Unfortunately, the narrator was still in an old relationship which he hadn't enough courage (?) to end up or was still hesitating at that moment whether he wants to stay with the old partner (and old life). So, the narrator was unfaithful to someone and to a certain point he is aware of his actions. That's why he calls it hell. He knows he has done something terrible, but he couldn't help himself. When he opened new door (love affair, new love), he probably closed the old one (old relationship). He hasn't done it the right way, but when you decide to cheat on someone, you don't think about the consequences so much, it's just a moment, you just want to seize the day. All those hostilities are probably factors from his old life like e.g. friends/family who try to convince him to come to his senses, his old partner left behind or new factors who appear when he decides to start a new relationship (the impossibility of being together because of long distance that divides them, their old careers, work commitments). A moral: don't cheat. Ever! And don't let you Id take control over your mind and body.