Help!!! 6 week old still not sleeping!

Any tips?! 6 week old EBF is still only sleeping 45 minutes to 1.5 hours at a time. My DD can eat up to 4-6 ounces per feeding as well... I produce pretty well, after feeding my daughter I can still pump about 3 oz. If she bottle fed by her dad (to give my boobs a break) I will pump and I always put out between 5-8 ounces. Starting to feel like I'm not sure how much longer I can survive on this little sleep. I want to continue to breastfeed however I have been told numerous times switching to formula she will sleep longer and eat less frequently!