is there space to put the sectional where the current couch is but with the other side opposite of the sliding door and window? Maybe a sectional is just a poor choice for this room?

Could you put the TV on the wall opposite the fireplace (where the couch currently is) and then have an L-shaped sectional? (the "short" part of the L floating in middle and the long part facing out? do you know what I mean?) Just a thought! Not a pro! :)

It looks as if the room as large enough to have two seating area's ( unless it's just a camera lens illusion. )
You could put a sofa facing wall opposite the fire place. Mount the TV on that wall .
Have a sofa table behind sofa with table lamps. Facing the fire place have two comfy swivel chairs . Great cozy reading area and you can swivel chair to face TV when wanted.
You still seem to have enough space to have an armchair on either side of the sofa or at least one.
You could lay this out on your floor, marking it with painters tape to see how items fit.

Sofa/chaise opposite fireplace:

Darzy nailed it, but get your sofa with the right facing chaise so the chaise is opposite the sliders.

Also consider having a console custom made for the right side of the fireplace or even doing some kind of built in instead of that little shelf thingy so it all looks intentional.

Oh hell, why not rework the whole wall?

I would leave sofa and coffee table just like they are and get a couple of nice club chair/ recliners to put in front of the fireplace and put the tv where the chair is now to the right of the fireplace. You could move the chair to the area where the sofa is. With the doors where they are, I wouldn't use a sectional in this room. It would not have a cozy feel on either side of the room and almost look like an elephant in the room. You could get a side table and lamp to put on the outside side of each club chair and leave the opening in the center so you could see the fireplace if you're sitting on the sofa.

Not that color or anything just something similar to it.

Hey guys thanks for all of the comments. The fireplace is definitely too far away from the wall where the couch is currently to use those existing placements. The other problem is that the exit to the backyard is the left side of the slider door and I don't think we would want to block it. If the couch floats in the middle of the room we block the slider, if we put it in the back corner and have the TV on the wall (which is the backside of the kitchen), we also block about half of the window/slider. It's tough! So no one would use the wall across from the slider? This is my first home and I feel completely incompetent/amateur over here. It's a horrible feeling!

Here is a better pic of the wall opposite the slider doors where we have an option other than over the fireplace. As you can see it's too far to sit against the back wall and watch tv if it's over the fireplace. A corner sectional that fits in the corner and has two sections from corner sticking out, will block up to the middle of the slider but not the actual door.

Ok, just throwing this idea out there: could you put the TV where the mirror currently is and then have the main part of a sectional against the wall that faces the sliding doors (the backwall of the kitchen)? That way the sliding doors are still easy to access and your main seating is convenient to both the TV and the fireplace.

Would you post measurements of the room, then I can work up a floor plan for you

Eliminating the sectional idea will solve some of the problem. Just get a comfy sofa and pull it away from the back wall a couple of feet with the sofa table behind for lamps. Then, two swivel chairs floating facing the sofa, or turned to watch television. If you need more seating, you can put a bench on the hall wall.