To feed or not to feed?

My 4 month old baby used to sleep ALOT longer than she does now. At 2 weeks, we was sleeping six hours in a row (10pm-4am), and by six weeks she was sleeping a consistent 8-9 hours in a row without waking. But now I'm lucky if I get 4 hours in a row. This has been going on since she was 12 weeks old. (now 19) I've heard of the 4 month sleep regression, but we have been dealing with this for almost two months now. So my question is should I feed her when she wakes up or not? When I feed her, she goes right back to sleep very quickly, but I know that in the past she was able to go alot longer between night time feedings. I tried giving her a pacifier to stall her, but it just makes for me going to here every 30 minutes. I'm just so confused on how to handle this. I don't want to 'starve' my baby, but I also don't want to create a habit. Any suggestions??? I feel like I am going crazy by the lack of sleep. I was up every single hour last night! (and have been for the past 7-8 weeks!)