I recently created my own follower. If I revert to a save just after I get him, he will answer me fine.

But now, after about an hour of wastelanding, when I talk to him he says the correct line "what do you need"
However, he won't continue, he'll just sit there with that text box up.
The game isn't frozen, the dialogue just won't continue...
Suggestions?

If you created your follower then perhaps you made some sort of mistake? That is the only reasonable explanation I can come up with.

I have no experience in using the G.E.C.K. so I don't know what to do to fix it

Are you using a quest dialogue method or did you try to script his dialogue?

Yes I am using quest dialogue

I assume you added the 'GREETING' topic to your quest. Did you make other topics that have the 'top level' box checked, so they show after you greet your follower?

Also, i've read that dialog can lock up if you use the 'add topics' area in the GREETING dialog, instead of using the 'top level' box in your other topics.

I have not used top-level for anything, and did not use the add-topics box...

How did he get dialogue?

He's talking about the add topics box to the right of the prompt box

I was unclear. I meant how did your NPC get dialogue?

I'm still not 100% on what you mean...
He gets his dialogue from a quest, starting with a GREETING topic

If you start the conversation with the NPC by adding a line of dialogue to the GREETING topic, and you want the dialogue to continue beyond a single comment, then you have to create additional topics and add their EditorIDs to the box on the right that is labelled "Choices". If you have several resulting dialogue topics in the Choices box then each topic should display the player's next possible lines of dialogue for selection in game as soon as the NPC delivers his line. Those resulting topics can also have choices so that the dialogue can continue with possibly different outcomes. If there are no additional dialogue choices for the player then the "Goodbye" box should be checked in order to end the dialogue.

Lol I know how to create dialogue, I've got 3 quests with over 100 lines of dialogue. The problem I'm having is that my follower is not continuing past the Greeting. The box that says "What do you need" just stays there

That bit of information would have been appropriate in your first post. You were, and continue to be, vague about what you have actually done to get into this fix. If your thread is going to require digging for nuggets of information in order to help you while being laughed at for telling you things that you already know but did not bother mentioning, then, well... "Homie don't play dat."

Sorry,I didn't mean to offend you. I do suppose I was too vague. Here are the key points:
1) Follower begins as a captive, you rescue him, and he feels indebted to you and follows you
2) He was constructed following (with some changes) this guide and prior knowledge http://www.gamesas.com/index.php?/topic/1011099-tutz-companionfollower-tutorial/page__p__14624433__fromsearch__1&#entry14624433
3) He exhibits proper behavior (greeting, followed by choices like view inventory and follow/wait) immediately after the rescue, and for a short time after
4) I noticed after about an hour that when I talked to him, his greeting shows up, but stays up indefintely until reload
5) I voiced him, but my voice does not play; only the words show up and stay up
6) All other people's dialogue is normal

I hope this helps, and sorry again

Utilizing a bump

If you stuck to that tutorial, your dialog should work.

item 4 - do you have other companion mods - try unticking them in FOMM. They will most likely use GREETING also.

item 5 - do the sounds play when you double click on them in the Geck? They may be in the incorrect path. Did you make the sound files yourself? You might try removing them to see if that's the problem.