It's really OK & normal for a newborn baby to want to wake & nurse that often! When he's older (maybe 6 months, maybe older), you can worry about his sleep, but for now, let him tell you what he needs.
It's tough that you have to go back to work so soon, but great that you're committed to breastfeeding! It's often hard to keep up your milk supply when you're working--it's easy to skip a pumping, and since pumping stimulates the breast less than your baby does when he nurses, before you know it your supply has gone down. This happened to me when I went back to work.
I've been told that we produce more milk at night so it would be important to nurse on demand at night. Since I've been doing that, my milk has been plentiful, even during the day. Other things that can reduce your milk supply are stress, including lack of sleep. Many moms find that co-sleeping and nursing on demand give them more sleep and I just read a study in a nursing journal that verified that; and I find that has been true for me, at least. Even hauling baby out of the co-sleeper and putting him back was more than I wanted to do, much less struggling with any kind of sleep-training.
BUT, some people swear by sleep-training; you might give it a try. Get some books on it--there are many--because there are a lot of variations on the theme. We learned a lot from The No-Cry Sleep Solution and Sleeping Through the Night. But our baby is 7 months old. I wouldn't have tried this before 4 months.
Our kid loves to eat and we never had a problem with the bottle. But, this was our midwife's advice about bottle-feeding: if your baby has a pacifier he likes, find a bottle with a nipple that is most like the pacifier. If not, get several of the ones marketed for newborns and see if he likes one. It sounds like the baby wants to nurse for comfort and closeness to you as much as for nutrition. Be sure that your baby can't see, hear or smell you when your husband gives him the bottle--go out for coffee! It might also help to have a lovey--a blanket or something that he can hold that you've slept with for a few nights so that it smells like you; even t-shirt you've worn will do. It will help him sleep too.
If it does end up that your milk goes down, try to nurse as much as you can, because he'll get good immunities from your milk, and after having been apart for many hours the closeness of nursing will probably be nice for you both. But don't stress too much if you have to supplement or even substitute with formula--lots of kids are fine with it. But I hope you're able to breastfeed as long as you want! Good luck!