Retaining the La Liga title is not impossible for Barcelona, but I admit that their chances are getting lower. Real Madrid is much more consistent than Barcelona and that is the reason why Barcelona is having difficulty competing in La Liga this season. If Real Madrid loses points in several matches in the remaining season and Barcelona is able to take advantage of it well, then the title competition between Barcelona and Real Madrid will happen again. It's not impossible, but it's difficult.
However, I tend to agree that Real Madrid deserved to win the La Liga title this season after they performed well from the start of the season. Barcelona is struggling with its squad and finances, so it would be a shame if Real Madrid failed to win the title this season and let Barcelona defend it.
Barcelona becomes very prominent the moment they shifts points closer to Real Madrid and Girona but it's impossible for the Blaugrana to hanged on Los Blancos and Gironistes. Barcelona have fallen from the top this season, they failed to hits the key areas, meaning they sits in good position of winning average teams in league matches but they misused their chances and now they're paying the price of underestimating ratio. However Barcelona coach, Xavi Hernandez made everything clear and plane, he's leaving Camp Nou at the end of the season, he looks forward in pursuit of his new career.