heart broken

so I'm 20. and my boyfriend is 25. we have been together a little over a year and a half, and known each other a little over 2 years now. I've never loved someone as much as I love him. since the moment I saw him I knew I needed him.. we've always had little arguments that would result in him thinking I'm not happy and we eventually got better. I just got off birth control and we were talking about wanting kids and everything. recently he's been very depressed and I been doing everything I can to keep him up. I just quit my job so I'm down.. then tonight he tells me he feels like our age difference isn't good. that we are at 2 different stages. which I understand but I don't. I do mess up and make a lot of innards choices but like 2 years? all this talk and love and memories? IDK what to do I'm just hurting so bad.