2 in diapers? Regression Hell!

My 2 year old has been potty training since last November. She did really well right away. She can almost always go on the toilet if she is reminded and she was starting to go by herself. Then in January we told her she was going to be a big sister. She was very excited but immediately started having tons of accidents. We tried to not talk about the new baby as much, did a sticker program, things were going fine. She would still have occasional accidents, I would never say she was completely competent with using the toilet, but maybe one accident every week or two. Well when people started talking a lot about the baby, the accidents increased and now that her new brother is her she has started having several accidents a day. She has even told me it is because she wants to act like a baby. She will sit there and stare at me and pee on the floor. Well I tried not to make a big deal thinking it would pass, but now her brother has been here for over a month and I finally couldn't take it any more. I put her in pull-ups but we talked a lot about using the toilet so she could wear her big girl undies. I really didn't want to put her in pull-ups because they are too much like diapers and she didn't want to put them on at first, but we were traveling and she had already wet her carseat without even a flinch. Now to be fair, I don't think she likes wetting her pants, but she really seems to have no indication that she has to go anymore. Is this normal? So anyway, we convinced her to put the pull-up on and that was fine for a few days, she did well keeping it dry. Now today she has been wet every time she has gone to the bathroom. I asked her why, she said it was a diaper and it was meant to be peed in. Grr!! So I asked her if she wanted to start wearing diapers again and I would put the potty chair away until she is ready to use the potty again, she is adamant that she does want to use the potty. When I was digging through a bin looking for the diapers I had put away nine months ago I found some rubber training pants I had so I decided we would try that for a couple of days and see if them being more like underwear would help. But I am so ready to just give up and put her in diapers. Would this scar her for life? I had heard people talk about older siblings regressing when a new baby arrives, but I didn't think it would last this long, and I didn't think I would find it so aggravating. Any advice or experiences would be helpful. This isn't the only behavior, she wants to act like a baby in many other ways, talking baby talk, laying in the crib, wanting her cup like a bottle. But these things only happen occasionally, this wetting and messing her pants (she has rarely if ever messed her pants since she started using the potty) is not going away.