Struggling with relationship

[Estalocovida]

Hi everyone,

I just really need some help or advice here please! I've been with my boyfriend for just over a year now, I know it's not long though. However I'm 23 and he's 28, but he is really really immature, not as in messing around or playing the fool, I mean childish! Such as whenever we go to theme parks he runs off to the rides, or in stores he runs away and picks up everything to buy. He's a lovely guy and loves me a lot and I still do love him, but I'm really struggling to stay happy in this relationship, I've totally lost my independence as he wants to be with me everywhere I go. I havnt saved any money since being with him and I know he hasn't as he can't stop spending and buying things on groupon, as lovely as it is, it's just getting too much more me as I really just want a mature relationship but I can't see it happening with him. I've thought about leaving him but I know it will break his heart and I don't ever want to see him upset. HELP!