When I think someone else might have a problem with something I want to say, I like to pass the responsibility back to them. In this case, for instance...

I don't want to talk about it because I'm scared she will think I'm disgusting.

...I'd think of going "meta" (having a conversation about a conversation) and asking her something like:

"If there were something I wanted to tell you but I was afraid you'd think I was disgusting, what would you prefer that I do?"

Do you think something like that might work for you and your T?

I actually feel like the feelings of worthlessness are valid. Maybe she wants me to articulate the feeling of "screwed up" better?

I'd guess that that was it: if you want to give her something definite to work with, tell her you think or feel you're screwed up, but also exactly how you know that.

I have a feeling that it would also help you get a handle on feeling worthless or screwed up if you paid close attention to where you were looking. For example, if you were to get the idea that someone else must think you're that way, you'd notice that you really had no way to know what they were thinking but that you were thinking they might be thinking that. Then: is that the only thing you can think, or do you have a choice? Can you, for instance, imagine that they must be screwed up to think that of you, and notice how it feels to imagine that? Then get the idea that they're thinking nothing of the sort but you made it all up, and see how that feels to you? My guess is that the more practice you get thinking all kinds of different things from all kinds of different directions and noticing how you feel, the more you'll get over any fear you may have of thinking some of them, and the better able you'll be to think what suits you best.

I know she wouldn't want me to be thinking critical things about myself, but I just don't know how to make them stop.

That sounds like something else you could ask her advice on:

"When I find myself thinking critical things about myself, what do you recommend that I do?"

It sounds like part of her job to help you let go of doing that, especially if it interferes with the rest of the work you're doing together.

I know my T would like me to talk about it more, but she wont push it and she wont bring it up

My guess is, she thinks it'll be easier for both of you if you bring it up when you're ready than if she presses you when you're not. I used to wonder, "How do I tell when I'm ready? What if I only think I am -- or only think I'm not?" Lately, though, the way I usually tell that I'm ready to do something is -- I notice I'm doing it.

(Sometimes, of course, I find out I'm also ready to stop doing it very soon after I start )
I have a feeling that you trust her and you don't, and it'll be easier to live with both of those once you can experience them at the same time. At times I've thought of it as holding one in each hand, or standing on one with each foot.

Again, good luck and let us know how it goes.