I am in the middle on this one. The problem goes back to the expectations that a LBS can have with these kinds of invites. IF you can invite her along to things and assign no significance to whether or not she comes, then I don't see a problem. However, it should be infrequent, and should be because you are taking the kids, or maybe meeting mutual friends, etc.
Most of your activities should be on your own.
Most of the time the best approach for calls is to let them go to VM. If no VM and/or no followup text then it probably wasn't that important.
Obviously with VM and texts you can respond to direct question in your own time.
On messages, if it is informational then there no need to respond. You aren't ignoring them, ignoring them would be to not even listen or read them. If she asks a direct question, then respond with a text to the question in as few words as possible. Yes or no questions get yes or no answers.
Avoid the temptation to include courtesies. "Thanks for texting." "Good to hear from you.' "Bye for now." Stick to business and strictly business.
If she asks a question you don't want to answer then put her off for now. "I need to consider this some more before answering." That is a perfectly good answer or something similar.
Hope this helps.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018