Why is dating so hard?

I am 42M, single father of 2, ages 13 and 8. I have my kids about 90%+ of the time. 4 years single after an 11 year relationship. I am just getting back out into the dating scene again. This seems next to impossible, and I am really curious how others handle it.

I just started seeing a woman my age, who is also a single parent to 2 kids, ages 9 and 15. We can barely find 15 minutes in the evenings to talk, which is barely enough time to even ask each other about our days. We see each other less than once per week, which we have to choose as either a date night, an intimate night, or a family night (to explain that... if we can only see eachother once every 2 weeks and we are craving intimacy, then we are getting a hotel room and getting room service. If it's date night, then we will do diner and some kind of activity, but that doesn't leave us anywhere to go for intimacy. And if we do a family night, then we save money on babysitters, bring all the kids together for a movie or something, but again, no place for intimacy). We have a ton in common and we can talk for hours. There is chemistry up the wazoo, and the intimacy is top notch when we can find the time and space for it. None of these limitations are due to a lack of wanting more, but babysitters are expensive, we live an hour apart, and we have to manage our work and home and kid schedules first.

There is no daily flirtation, no cute texts. Once in a while on our nightly calls she will say something flirty, but that's about it. I tried to send some flirty texts and got told not to text her that kind of stuff because her kids look through her phone, so I should send her those kinds of messages over SnapChat. I tried that, only to find that she has notifications turned off for SnapChat, so I have to then send her a message to check Snap... To me that feels like it kills the fun, playful spontaneity of sending those kinds of texts. I did tell her I felt that way, but she didn't respond (I'm sure she meant to, but with so little time to actually talk, a lot doesn't make it to the final cut.

Are my expectations of dating at this stage of life way off? I want to feel the passion and the heat I felt in my relationships when I was younger. Is that not realistic anymore? Are we doing something wrong or is this just what dating is like at this stage of life?