Why won't they send in more NATO countries, after these months, to help Ukraine regain land from Russia?
It makes sense that they won't allow their own skin to be ravaged (United States, Britain, Germany, France etc), but why not the Baltics and Poland, at this point?
I'm surprised they haven't done so, after these long months
Because that would be looked down on. You can't just send in an army to take part in a war you are not a part of. That is only allowed if you have a defensive pact with said country. If NATO could just join any war it felt like it would have directly joined the chechen war in the 1990's.
Just to clarify, you are talking of the first civil war, right? Also, they may have not sent ground troops, but they certainly sent air support, through no fly zone and aerial bombings of the country.