Mom of 2 over 40 tri-ing to get fit

Hi all, I've actually been on this forum for a very long time and have yet to actually accomplish a triathlon. I have run several 5Ks, 10Ks and 2 half marathons. I was training for the Hamptons marathon when I found out I was pregnant with my 2nd child. I have signed up for a bunch of tris in the past to overcome my fear of the water. So, 2 babies later, I'm again starting over. Here's a recap on me--

Live in NYC/work on LI
work full time- 12 ++ hour days some time, some weekends
commute 1 hr each way
43 year old mom of a 1 year old boy and 2 1/2 yr old girl. my angels and motivation to stay fit and healthy

All that to say my training time is pretty darn limited. My time with my kids is so small and so precious I don't want to take much of that time away from them. But I have developed the worst case of a spare tire ever- and I'm otherwise petite and small so it basically looks like I'm still 7 months pregnant. I've had people think I was working on baby #3.

What I have accomplished: I now can swim a little. I couldn't swim at ALL when I first got on board. I still have to stop every 50-100 meters to catch my breath. But I am moving forward.

Any middle aged moms in my situation?