I've been playing guitar on my own for about a year.

The past few months I've practiced more and more and got to the point where I could play decently fast licks, but they are just muscle memory.

I don't know much music theory and my ears arent trained very well, I have been using tabs all the way.

I want to be able to improvise well and play freely not just being able to play a few licks very fast that Ive played 1 million times in a row.

I practice hard, and consistently, and I keep working at something till I achieve it. SO how do I go about reaching my goal? I cant get a teacher right now either.
3 billion guitarists get told that by their teachers every day...

Too bad the teachers are right, assholes...

Epiphone G-400 Vintage SG
Marshall MG Series 30DFX.
ESP LTD AX-400 (My baby)
i was in the same position about 3 months ago

first i set off my speed of playing which it sounds like you have already done

then i learnt a whole scale, i learnt A Minor Pentatonic (its on the lesoon part of UG)
Learn all positions and how to change keys while using the scale

Then improvise over a song in that key

Now ear training is where it can be difficult if you can't do it right. Its easier to do it with a friend as you can't cheat

Get a friend to strike and open chord, to identify it find the bass note, if you can't find it ask them to play it again and try to find the bass note on your guitar

do this until you find the bass note, then the whole chord will come from what you remember about the chords in that bass note

Thats all i can really say
it will take time so keep motivated and practising

and only use tabs as a guideline to what it actually is,
They are very rarely right all of the time

Hope this was of some help
I have being playing for about 2 and a half years and when i first picked up a guitar i learnt from a book. So basically i learnt my Basic Chords. Then i used those basic chords to play a few rock songs. T.N.T, wild thing and etc. I then bought books on scales, diiferent chord shapes and tabs and research on the inet.

I take it that uno ur basic chords. so just do things like what notes are in those chords, figure out how to make that same chords some where else on the neck.
With scales, start to learn the minor pentatonic scales and from there u can build onto the bluse scale. The only way to play and become a pro is to practice practice and practice and to know as much music theroy as possible.

I am obviously not an expert on music theroy and things, but for the last 2 years i have learnt most bits off my own back and books. But be careful if you are willing to learn ur self, beaware tht there are great chances of making mistakes if ur not learning properly!!

Hope this helps!
Start transcribing songs you like. You'll work on your ears and learn new material at the same time.
(Slightly outdated) Electronic and classical compositions by m'self: Check 'em out
^ is a really great way. thats what i did, although for beginners i recommend learning some songs first before you start trying to attempt to transcrible them (i did at least, i needed some basis of reference, i learned a LOT of songs before i started trying) and then once you think you have it transcribed right check it against actual tab (i recommend either getting the actual tab book or checking it against multiple high rated tabs online)
Thanks for the help guys, I appreciate it.

So how do I know what key a song is? Can the key change mid song?

Also is there some place where I can get generic chord backing tracks, so I can start playing over them like you said?

Quote by a19e86
Thanks for the help guys, I appreciate it.

So how do I know what key a song is?.

this is the rotten part. initially you don't, after awhile your ears will start to recognize chords, chord shapes and notes but initially your best bet is to find the first chord of the song and figure out if its major or minor. after that you can usually use a combination of your ears and theory to figure out the chords coming after that chord.

Quote by a19e86
Can the key change mid song?

yes it can, i recommend starting real simple at first, nirvana, ac/dc, stuff like that (that has few if any key changes, i can't think of a song from either of those 2 that changes keys)

Quote by a19e86
Also is there some place where I can get generic chord backing tracks, so I can start playing over them like you said?

i'm sure there are but i have no idea where. i recommend recording your own, either on your computer or even a crappy $20 radio shack tape recorder. the reason being you can start as slow as you need to and work your way up AND you have a more intimate connection with the music since you actually did it (this is hard to explain, but more or less, your hands and muscles went through the steps of laying down that D,ABm and G chord progression so it will be a little more instilled in your brain and muscles)

i recommend starting off with a really simple 2 chord progression and following it until you feel you have a really really good grasp on those 2. then record another with a 3rd chord, rinse, repeat, add a 4th chord and so on and so on and so on. the principle is that it gets you thinking about what chord you're on and more importantly what chord is coming up.