Well, one can always hope that maturity will grow with age. At his age, he's already done remarkable things, such as fighting in Afghanistan, so if he is "sowing his wild oats" a bit, then so be it. If Chelsea is all that eager to settle down, then she'll have to wait a bit. Goodness knows that both of them are quite young, and they should both enjoy life for the moment. There should be no hurry for them to get settled now. They can still have a relationship that is meaningful while enjoying their own lives, and if all she wants to do is change him, then perhaps she is with the wrong person. Peoples personalities change as they grow, and she can either grow with him, or go off and find a much more mature gentleman, who will keel over long before she does.