how the use of text messages and social media has ruined the modern language

I would ask some more analytical questions here so that you can be a little more objective in the way you are examining the topic.  Rather than going right to your claim that texting is ruining the language, ask yourself why or how. Then consider whether there is a direct correlation between texting use and other forms of communication.  Finally, see if this is necessarily negative or merely an adaptation of language to a particular context. Whatever the conclusion–even if you still feel that it is ruining language–you will have a better idea of what you are claiming and why.