Text messaging help/ texting apps?

[Kasey B]

I have a LG Optimus G from Sprint. I cannot group chat with others. I can send out a group message, but the replies will trickle in from the recipients to a new text group where it is 1-on-1 with me and the rest of the group can't see the conversation. If I am included in a group text, I will receive the messages as an MMS, and the senders' messages will all come in as 1-on-1 messages. My sent messages cannot be seen by the group, but the group will still see the responses to my sent messages in group chat. I've gone through all of the messaging options and cannot find an "allow group chat" option. Any app suggestions?