>>1I'd say, and don't take it too seriously, I'm only a freshman, if you really lover her and think she's 'the one' then go along with her. If not, and I'm getting the sense she isn't, then go your separate ways. As for when to tell her, if she's the type to throw a tantrum and make your life miserable while she can, then don't tell her until later. If she's not like that, then maybe tell her after you sign the papers. If she has something against any decision you make, it's her own opinion and it can't affect you by this point.
>>2I'd say, again, I'm 14 and this shouldn't be taken into too serious consideration, talk it over with them. If you think it's best and easiest to move out, then talk it over with them. Lay out your cards perse and give it to them straight. If you can afford it, then help with their rent until they get it in their heads that they actually have to support themselves. If not, then keep reminding them about it so they can make the money for it until they do it on their own. You amy feel like you're nagging them a bit this way, but from what I can tell, they need it. If you think staying with them would be your best bet, then nudge your siblings into giving to the family a bit more and give a bit less yourself to force their hands a bit. This way, if you think it would be okay to move out later on, you can and they can help support your family in your place.
Well, I hope this can give you a bit of help and advice but again, I'm 14 so this probably won't be the best of advice.