svirac

We should remember to be kind on this forum to people asking for help.  Those of us here are more informed than many about the immigration system, which really is terribly complicated.  
 
For the OP, I think to summarize the advice, is that it would certainly appear to many people that you effectively abandoned permanent residence.   You're in a bit of a tricky spot, because while you've been allowed to return consistently to the US thus far any further scrutiny by CBP could lead to the green card being revoked.  The absences of greater than 6 month are really meant to refer to where your official residence is--just visiting the US doesn't reset the clock.  
 
I might suggest you speak to a competent immigration lawyer for advice.  This site is great for advice on DIY situations, but this one might be somewhat more complicated than that.

Does your wife ever plan on getting US citizenship? If she does she will probably have to wait a good 5 yrs from when you re-establish yourself in the US. See the problem you have is 10yr greencards are not automatically voided or surrendered when one leaves the US. To keep things simple- basically once you have a 10yr GC you can either surrender it when you leave OR have CBP stop you trying to enter with it and refer you to court who will then review what went on and either let you keep it or take it from you. Even failing to renew it at the 10yr mark does not make your status disappear. Its a weird system.... So keeping that in mind your options are:
 
1. She tries to enter with the GC. It seems shes been let in many times since 2010 so I dont really see any reason why CBP would stop you this time. Unless you are traveling with a whole bunch of stuff like you are moving or are otherwise acting suspicious. Once she is back in the US she should not apply for citizenship until at least 5yrs-- check out the requirements. No one should question how much she was out of the country when she renews the card in 2020. They may question it when she applies for naturalization however it only goes back 5 yrs. Taking this path means you may have to 'keep looking over your shoulder' every time you travel. Because each time she goes to CBP with the card she has theres a chance they see her travel history and try to deny her entry. Some CBP officers are aggressive and will make it seem like you cant get in, but technically they have to allow her in to see a judge. CBP cant make the determination she has been out of the country too long, they can only refer her to court. Typically people are given a court NOA and let go but in some cases they can send you to a detention center to wait your court date. The fact she used Canadian healthcare- which as others have said is only for Canadians residing in Canada- means she gave up her GC status to USCIS. So if she goes to court most likely they will strip her status. 
 
2. She can surrender her GC at the Embassy in Canada and you reapply for the CR or rather IR visa. This will take about a year. She can still travel as a Canadian to the US and should be let in for the standard amount Canadians get but theres no guarantee they will let her in every time. 
 
So you can try to hold on to the status she currently has- however if it is ever challenged she will be stripped of it. The safest thing to do is to surrender the GC and reapply. (NO CHANCE of getting SB1 here, its been too long and she used Canadian healthcare system which means she considered herself a resident in Canada). 

Just ignore such people with self righteousness complex.