[Theoric Windcaller]

Personally, I think that it wasn't nessecarily because he was lonely and exiled that Gollum was created, but I think Gollum was a fore-shadowing of the Ring. With Smeagol's possession of the Ring, Gollum was created, and Gollum was growing more and more every day, that soon it led to his exile.

Now, I also believe that even though in the end, Smeagol gave into Gollum, that it showed that for a while in TTT book, Smeagol had beaten Gollum, so that says right there that Gollum grew powerful yes, but not too powerful.

See, Gollum was driven by his lust for the Ring. Now, once he lost the Ring and met with Frodo and Sam, he truly was intent on helping them to Mordor, but as they neared the Ring's destruction as they treked more and more into Mordor, the Ring took its toll on both Gollum and Frodo. Frodo was growing weaker, becoming more vulnerable to the Ring's power, and Gollum's lust was only growing more stronger, and that was what gave Gollum power and motive over Smeagol.

Smeagol was lost, between the two hobbits and the Ring, and with the rising power of Gollum, he fell more towards the Ring.


That's my two cents. (BTW this is IMO)