Deafblind people are not destined to lead a poor excuse for a real, happy life. Apparently, this is something that needs saying, at least in the Netherlands. Anne Baker said it to a doctor just in time to prevent stopping the life support of a deafblind infant.
In the Netherlands vierhandengebarentaal (four hands sign language) can be used by doofblinden next to NGT or other communication means. I once witnessed the preparations of lessons in this sign language. A group of deafblind people gathered to act as counterparts of hearing students. Obviously they were having a good time, enjoying each others company as a group of friends would. Their communication amongst each other and with the hearing teachers was not without difficulties but then again, so is mine with many people.
You can check some online movies.