Lets start by saying that the phone in and of itself is “mukzta” on Shabbos and should not be touched or moved. It has a battery like any child’s toy that you would not allow a child to use on Shabbos and therefor it is NOT permitted on shabbos. Therefor texting on that phone is not permitted on Shabbos any which way you look at it.
Having said that, lets look at the texting problem. If you HAVE to check your phone and text on Shabbos, you have to look at the bigger picture. YOU are addicted to your phone and to texting!!! Even a chain smoker who is Frum takes his last puff at the last second before Shabbos, does not smoke all of Shabbos and then lights up the first opportunity after Shabbos. Somehow he manages NOT to smoke the entire Shabbos. How does he do that? Any other day of the week he can’t get by more than an hour without a smoke but on Shabbos he can do it.
Think about that. How does he manage NOT to smoke on Shabbos and more so NOT to ruin his Shabbos menucha by thinking about smoking? Is it a matter of priorities? Is it a matter of Kibud Shabbos? Is it a matter of loyalty to Hashem, Torah and mitzvos? Maybe all of the above.
So now the question remains who are you loyal to your phone, your friends or Hashem and his mitzvos? Is this a test? Will you pass or fail? Will you give into your yetzer harah or will you understand that your yetzer horah is trying to make you turn away from Hashem and the Torah. Yes, you can look for excuses and make up loopholes to break the rules. You can do that with texting because you heard from others, or with “gum” or with anything else that you want to jump on the bandwagon with. OR you can stay true to the beliefs you grew up with and even strengthen them when the Yetzer Horah comes knocking at your door. That is your choice and it is choices that you will have to make every day of your life.
BTW if you feel lonely on Shabbos, get into reading books and slip away into the stories. Start communicating more with your family. Invite a friend over for Shabbos. No one has to feel lonely on Shabbos.