N.B.
Hi K.,
I believe in setting realistic, achievable goals. I think that with where you are in life, fitting in exercise is a great challenge. I had been on and off for a few years. Then, I started very simply 1 1/2 years. I made myself complete 5 push ups (from the knees) and 10 sit ups every weekday morning before I showered. That was it. Once I had established that routine, I adding in a little more. For example, I have 2 5lb "dumb bells" so I added in 2 lifting exercises for my arms, just 10 repetitions each. Eventually I increased the number of sit ups and push ups. I then added walking 1 to 2 miles. My situation is different in that I started much later than you, meaning my boys were 5 1/2 and 8 when I finally returned to exercising regularly AND I live on a cul-de-sac so I can walk around the street and they are usually on the street with me.
Ultimately, I advise that you set goals you really can achieve instead of ones you can't. I know how defeating it can be to say "I'm going to do X three times a week" and then find you can't either meet that goal the first week or be consistent with your plan. That lack of meeting the plan can be such a demotivator. In my mind, It is better to do something, even small, and keep with it than to set larger goals that you can only meet on an inconsistent basis.
Good Luck!