I am losing my mind

I have been at home with two kids now for 5 months. The first couple of months were just adjusting time and then the summer came and I just treated it like any other summer. Now, teachers are going back to school and I am not. I don’t quite know what to think. I’ve been home so long now that it really doesn’t feel weird except that I can’t call some of the people during the day that I usually do. My problem is that I don’t know what to do now. I don’t have a car during the day and usually not at night either because my husband works late. My son thrives on social interaction and has been deprived of that since A came along. We just couldn’t continue to keep him in daycare. We can’t afford a Mother’s Day Out program this fall so we are all just stuck in the house all week. It’s too hot to take him outside and I have nowhere to put A if she’s awake and K wants to play with me. Does anyone have any advice to a new stay-at-home mom who is literally staying at home? K is driving me nuts because he doesn’t have anyone to play with besides me and the dog. Also, is it normal for a 2 ½ year old to ignore what you tell him and talk back? Maybe it is just because I’m frustrated. K comes by his love for being around people honestly. I want to be around people during the day, too. I don’t care if it’s just Wal-mart and I don’t know a single person there. At least there are other people around. I feel so isolated sometimes. So, if you are reading this and have some ideas to keep him occupied besides with the TV, help!!!