You sound really frustrated. I'm sorry it's so tough! :( High-needs babies are tough on a mama, and having another little one only complicates it.
In general, I'd say that what you're doing now isn't working, and you should look into other options. It sounds like there's more going on here, and I do not think that "sleep training" is going to be the solution. I agree with another poster who suggests there may be a physical issue, such as reflux, that is interrupting her sleep. While there are some medications available for reflux, the very best solution I've found (with three babies with reflux!) is chiropractic care. If you live in the Houston area, I can recommend some excellent chiropractors who are certified with children. If not, you should check http://www.icpa4kids.com/ to find one in your area. It has made a WORLD of difference, and very quickly, for my babies and those of friends.
I also recommend the book, "The No-Cry Sleep Solution," which can help you assess your needs, her needs, and your goals, as well as offering concrete advice and solutions to try. There is no one-size-fits-all solution, so having a host of ideas in this book is very helpful.
Do you ever "wear" your baby? Many high-needs babies find great comfort in being worn, and babywearing also leaves your hands free to tend to your toddler. Again, if you're in the Houston area I can connect you with great resources. Otherwise, check out http://www.thebabywearer.com/ for excellent information.
You may also want to reconsider swaddling with her. She's so very young still, that it may help. You say she sleeps only 30m at a time now, but slept 45m in the swaddling blanket. That sounds better, to me! :)
Another option that often helps high-needs babies to bring her into your room, and even your bed, to sleep. It's far less disturbing to anyone who does need to wake up to tend to a baby to have them nearby. As well, when nursing at night, it's much more peaceful to simply be able to nurse in bed and fall asleep again with the baby. Some safe sleeping tips: http://askdrsears.com/html/7/T070600.asp
Truly, a baby at this stage is learning to trust, and refusing to tend to her or give her a pacifier that she's fallen asleep with is not teaching her trust. She is NOT old enough to learn "consequences." I hope some of these other tools will help you deal with this frustrating situation, so that you can ALL get some more sleep!
Some more advice on sleep from Dr. Sears: http://askdrsears.com/html/7/T070100.asp