35 weeks pregnant and freaking out?

This baby was unplanned, and a huge surprise. I'm so close to having him now, and I'm trying hard to be happy and excited...i truely love this little kid. But I am so stressed with other issues in my life...a bad marriage, financial difficulties. And I am feeling a lot of guilt for not being completely there for my 2 year old, I know she won't have the attention she is used to having. I'm terrified that when the baby is born, I will get postpartum depression, and resent the baby.. I was trying to nap on the couch this aft, and everything aculated in my mind and I had a panic attack...I don't know where to turn. My biggest source of emotional support...my husband, has his own issues and has checked out when it comes to being supportive of me.