baby sleeping/full time working mom

Any full time working moms finding it hard to get baby to sleep all night. I've been back to work since the end of August and my LO is almost six months. We breast feed at home and she gets bottle breast milk at the sitter. It seems like she's waking ALL the time to nurse. Sometimes I feel it's just comfort. I read online it could be from me being away from her all day and she's just wanting me. Just wondering if anyone is going through something similar..