"So.... are you still seeing that Xavier guy?" Dally asked me shyly.
"Oh! Right I need to tell you something........ I'm kind of getting married to him." I sadly said.
"I'm happy for you," He said with a unenthusiastic voice. Then asked, "Are you happy with him?"
I sighed, "You know I'm not, but I'm doing good. I would still be on the streets if it wasn't for him."
"You could live with me." Dally quickly mumbled.
"Huh?"
"Nothing..."
I stared him in the eye and said, "I can't." He understood.
Let's take it sentence by sentence :3 Note, a few of these are merely opinion based, but most of my critiques will to enable easy reading, to help it go smoothly through the process :D
"So.... are you still seeing that Xavier guy?" Dally asked me shyly.
You have four little dots there ._. Four. Four normally means you having a drawl on the last word, or dragging it, either way. But it also means... and then a period, to end the drag. It especially means that because you spaced after it. All in all, it should either be a triple, or a quad, space, then a capital A. :3 And then 'Dally asked me shyly.'
I recommend changing that to something along the lines of 'Dally asked, shyly.' I assume the two characters are around no one else, so no need for the 'me', eh?
"Oh! Right I need to tell you something........ I'm kind of getting married to him." I sadly said.
Oh, is perfectly fine, on my terms. But it should be 'Right, I need to tell you something.'. You don't have that comma there. And then what is up with all those periods? ._. You have too many drags. You could pull a '"Oh! Right, I need to tell you something." I paused, {thinking over how to tell him.? I don't know how the character would act, but eh.} "I'm kind of getting married to him." {Then maybe a, hmm...This is the hard part of editing certain sections, I don't know the character yet D;. Maybe a, 'Even I could hear the sadness staining my voice.'}
"I'm happy for you," He said with a unenthusiastic voice. Then asked, "Are you happy with him?"
Too many happy's ._. Or is it how the character talks? I know one of my characters likes to describe everything he sees as 'beautiful' :3 I don't often use the comma-instead-of-a-period-if-I'm-continuing-rule myself, but I don't think that's used right :3 I think it should only really be used if you're saying something such as '"You're beautiful," Johnny said, eyeing me. "Really."' What I'm saying is...Replace the first comma with a period :3
I sighed, "You know I'm not, but I'm doing good. I would still be on the streets if it wasn't for him."
'I sighed.' Not 'I sighed,' Unless she was actually sighing out the words. ...I'm going to go try doing that ._. Other than that, really no critique.
"Nothing..."
Hun, again with the periods? ._.
Done, I believe :3