I am a SAHM as well. I have a 3 year old boy who finally potty trained and I am 3 months pregnant with my second child. I have always wanted to be a SAHM and thankfully my husband got a great job literally a week before our son was born.
Most family and friends support our decision and think it is absolutely great that my children will be able to have their mother around on a daily basis to care for them.
I know that some think that I am being oppressed, being forced to stay home or that my husband just tries to keep my home. None of this is true. I am a homebody and at my happiest when I am home (although I do enjoy an adult day here and there like any normal person). I also clean a dental office 2 nights a week just to get out and do something (plus some extra money for the family).
As someone who grew up with a single mother of two and was brought up in different day cares I can tell you first hand that day care is definitely not the place that kids need to be. My sister and I were treated very poorly and most day cares don't even require drug testing for their workers (as I knew someone on coke who worked at a "prominent" day care). Not all day cares are bad but if they could have their mother over a stranger why wouldn't someone chose to be a SAHM.
If you and your boyfriend know in your heart that this is best for your boys then it is nobody's business. Your children will grow up and realize how lucky they were to have a mother who was able and willing to stay home with them all day long. My MIL, BIL and husband are very happy that they were able to have the same set up as I do now with my son. Not once has my MIL regreted staying at home with her boys for the first few years (she ended up becoming a great nurse).
If you and your SO end your relationship then who cares as long as you are cordial for the children and they are happy. If my husband leaves me then I would have to look for a better job but we already agreed that I would stay in the house until I could get on my feet as that would be best for our children, they wouldn't be able to come with me if I was homeless...
Screw what others say. Make your boyfriend happy. Make yourself happy. Most of all, make your kids happy.