Not saying this is specific to the OP's situation, but I think it is relevant to the issue as I have seen it referenced a few times in the thread - "Once kids are involved in other activities you will really be busy sort of thing."
I think one thing that has really changed over the last 10-15 years or so is the amount of time parents feel it is necessary to be right by their children's side. I have been a teacher and a coach at the JH/HS level for 20 years. Things have changed..... A LOT. I am just stunned by the amount of time parents spend dragging their kids all over creation and attending every waking moment of their children's play time.
At least where I live, it is completely and totally normal for parents to attend every single thing their kids are participating in - from the time they are 5 until they are 18...... everything..... always. Regardless of distance from home, regardless of significance of the event, regardless of the need to miss work, or even just have a few minutes to themselves. I know a lot of parents that sign their kids up for 40 hours a week of baseball and swim team and..... whatever else. And then, they attend all of it (on top of their full time job, and house/yard work, etc.) I think it is flat-out crazy.
#1 - in my experience - it is just unhealthy for the kid. It sends the message to the child that their "play time" is the single most important thing on this earth, and everyone should drop everything when they have a game to play. It places a disproportionate value on something that is just not that important.
#2 - it does not allow kids to learn how to entertain themselves. Sometimes kids just need to be on their own a little bit.
#3 - It has to be crazy for the parents and their lives....... every person - husband, wife, child should have time that they do things that are just theirs, and on their own. It let's people recharge and enjoy themselves with something that is theirs. If 24 hours of every day is scripted like a job.... what is the point?
I often have parents ask me (as a coach) what they can do to help their kids in the sports I coach. I tell them this: If you really want to do something for your child, pick at least 1 meet or game per season and say this to your kid:
"Good luck at your meet tonight. We can't make this one because we have some things we need to take care of at home (or we are going to do something else). Do your best, have fun and I am sure you will do a great job. Bye."
When they get home, tell them that you are proud of them for doing the best they could, and that you hope they had fun...... at that is it.
As kids get older, and are involved in things they like to do, that is not another "job" on a parent's plate. It is a chance to do something you like. Teach your children that having hobbies and enjoying life is healthy. It is something to do as children and as adults. Don't make their activities your "job" (which in turn ends up making their activities their job too).
Skip that track meet once a month and brew a beer. I will make sure your son or daughter has a great day "playing track." You have a great day brewing a beer.
Again - not saying this is the OP's specific situation, and not saying anyone should ignore their children as they grow up..... but, I think the key to a healthy, happy life for everyone is finding that place somewhere in the middle that allows everyone support and attention, but also independence and enjoyment.