I think it's great that you are going - you have to do what's right for YOU.
But, I would also suggest that you don't look at her comments and actions as trying to control you (or guilt tripping you). Instead, realize she is trying to control HER life. She's going blind, she's in assisted living where others have the upper hand, and the only time she can visit with friends and family is when THEY determine it's time.
Realizing that and making an effort to give her some control of her life back could make your decision a lot more positive. Something like, "Mom, we need to do this for us, but we're not abandoning you. We will come back for a visit X times a year, why don't you help us pick when those visits will be? Why don't you decide on a schedule for skype/phone calls every X days?" Then let her pick a day of the week and time of day for those calls and whether she wants your visits to occur on the holidays or during the times when other folks tend to forget to visit? You can set limitations (only in summer months, only 2 visits per year, only 1 week visits, etc.), but let her have some control as to when.
I just remember my dad when he couldn't get out anymore. He would sit alone for weeks and then would have 5 visits in one day (usually right after he got sick or something) and then sit alone for weeks again. He enjoyed the visits, having so many at once just made the rest of the time extremely lonely. Then he'd get demanding with us kids to come over and help. I tried to coordinate visits from folks to spread it out, but it seems everyone was more concerned about their convenience than his needs - but they always looked caring when they showed up after a hospital stay.
