Congratulations on bringing your new baby into the world. Since you are in your 30s and you are concerned with attachment issues, I’m guessing that this was an all the more special event in your life.
First, please take a look at the research on attachment outcomes for babies who are in daycare. They generally do as well or better than babies who are not. Babies in childcare do know who their mothers are. By six months, babies are secure in their attachment to their moms, especially when the moms do as you are doing while they are on leave — spending a lot of time and having a lot of contact with their children.
What you can do to ease both of you into your eventual return to work is to gradually start spending some time apart. You may already be doing this. Put your baby down in a baby carrier or a comfortable made-for-baby cushion for short times during the day. Give him some experience with you putting him down and then coming back. Allow your friends to hold him and play with him at times so he gets used to interacting with other people besides you. Since you are breast feeding, start doing some pumping (and stock piling milk in the freezer) and introduce a bottle for a feeding or two when he is six months old to get him used to it. Talk to your pediatrician or a lactation specialist about how best to do this.
It will be hard at first to leave him. You are part of an attachment couple after all. But do remind yourself that providing for him financially as well as emotionally is part of what will keep him safe and secure. If your work is part of what makes happy, he will also have a happier mom. To keep the emotional attachment going, all you need to do is establish a relaxed and attentive routine as you get ready in the morning, play with him between when you get home and bedtime, and enjoy your weekends together.
I wish you well.