He says he loves me and talks about when we have children and live together. Sometimes this seems really romantic, but mostly, I feel under pressure because I don't know what I want yet. Very few people stay for ever with the first person they have a relationship. Some people can feel trapped in a relationship. People who stay together just for the sake of 'being together' or because it seems like everyone else is in a couple may not be happy or be good for each other.
Relationships break up for lots of reasons.
For example, because they get too 'heavy' or serious. Or because one of you feels used or because you want to do different things. It can be difficult to break up because you may feel upset and feel like you're hurting someone. But sometimes it may be a relief for both of you. It stands to reason.