I am in Chiang Mai, have a TM 30 slip in my passport, stayed outside the province in hotels on several occasions, never reported this to immigration and (so far) don’t have a problem with 90 day reports or visa extension.
One addition to Tods advice: If you surrender yourself to the authorities you will probably be able to still clear overstay without a ban however if you get arrested or caught otherwise it could result in a 5 year ban so you might want to get this sorted ASAP.
If your husband is over 50 it’s relatively easy to get an visa/extension of stay. This can be renewed yearly, you as his wife can get a dependent visa/extension of stay. However working IN Thailand is prohibited. You state he flies in and out of the country so should be no problem for him, your online business might be not within the rules however here in Chiang Mai there are literally 1000’s if people working online from Thailand and the vast majority doesn’t have a work permit. It’s still a risk though.
Between 14 and 7 days before due date you can do your 90 days by post, you don’t have to send your passport just copies of main page, visa, arrival card and tm 30. Send them together with your last original 90 day report, a self addressed envelope and filled in tm47 form to:
Notify 90 Days
CHIANG MAI IMMIGRATION
Building A, G Floor
Promenada Resort Mall
192 - 193 Tambon Tasala,
Amphur Muang, Chiang Mai
*****
Have done this several times, i use EMS to send and just a normal 3 Baht stamp on the self addressed envelope. It takes about a week before you receive the new passport slip.
Martin Keough when they returned my second last report by post they even included a letter with their website encouraging to do the next one online. I tried but as already stated it didn’t work for me even though I was well within the time frame for online reporting.
I did 4 consecutive online reports before they took the whole system off line last year. After I read it that it came online again a few months ago I tried again both for myself and my wife, no luck this time but I have read that others were successful in Chiang Mai. For me reporting via snail mail is a better option.