Hi H.. I can relate to your situation. My son will be 3 in March and I have a baby who is 13 months. My older son isn't intense, he is actually super mellow, but he is 2 and will soon be 3 and those can just be really frustrating ages, even when your child isn't intense! I hate the way I talk to my son sometimes too. I have had some days (sleep deprived days - our baby isn't a sleeper either) where I feel like all I do is yell. I have made some real attempts to just not yell about stuff unless there is a real reason to do it. Even when my 2 year old is pushing the baby (which happens all the time) I have been trying to keep my cool. A deep breath really helps (if I have time) and sometimes I just remove him, rather than try to correct his behavior. I also try to get my son to ask me for help, rather than pushing, and then try to be there right away to move the baby so he understand that asking for help gets a response. This has helped some too.
I think it is harder for kids when their siblings start to become little people instead of just infants. My son when through a phase of indifference when the baby came, but it was really hard when Joey started to crawl. It was like all of a sudden Charlie realized that this person was going to affect his life more than he thought and it was an adjustment. It's much better now. I've heard that when the young one reaches about 18 months it becomes SO much better because they can actually play. Keep that in mind too, as it's only a few months away for your kids.
I also really recommend an ECFE class if you can find time in your schedule. If you are not familiar with the program, it is through your school district, and is a fantastic way to meet other Mom's in your area with kids your age. I have a few friends I met when my son was an infant that we still have play dates with nearly every week. We live in the Roseville district, and our school has a "sibling care" so I take a class with each child, and drop the other one off for the 1 1/2 hours of class time. It is fantastic. I get some quality time each week with each of the boys, and our classes also separate so we get some parent time as well. During the parenting time we usually have time to discuss the challenges we are facing as parents. This really helps me as well. I highly recommend the program. The fee's are based on your income, and are very reasonable, in my opinion.
I am also really trying to start working on getting my younger son to sleep better. We've been trying to put him down awake (he nurses before sleep, so sometimes that doesn't work if he falls asleep), and I've been trying to cut back on night nursing in the hopes of him sleeping better (not waking to nurse). My husband and I have an agreement that if he wakes before midnight, it's his job to get him back to sleep. I try to be in bed at 10, then I don't usually have to go in to him until 2 or so... on a good night. Anyway... little changes might really help with sleep, maybe you can switch with your husband every other night (if that works for your situation).
Sorry this message got so long! I just totally understand how you feel. Good luck. If you live near Roseville and are looking for ECFE info, or a playdate feel free to contact me with a personal message.
J.