First things first, don't worry about not being able to play barre chords... they don't get used as much as you might think, so for now, just relax and let go of any sense of urgency in trying to master them.
Next, approach learning barre chords as a completely separate part of your practice. Put a time limit on it, like 2 minutes. Spend 2 minutes of each practice session on it, and when the 2 minutes are up, stop and play something you can play & enjoy playing.
Start your approach by putting your guitar in your lap as if you are going to play. Now, stretch your left hand out in front of you (assuming you're fretting with your left hand) palm up. Keeping your hand relaxed, spread your fingers a bit. Now, holding your hand in that position, just bring it towards you & the guitar, and place your fingers over the fretboard. Notice how your fingers can reach across the fretboard.
You'll have to remember this relaxed position as you attempt to actually fret the barre chord. Its not particularly easy, so when you start to mess up, take your hand away and start over. Start with your index finger, place it, and play the notes you are barring. As you add each new finger, play through the notes and make sure you're fretting cleanly. Only add one new finger at a time, and check every time to see how that new finger affects the other notes. If you're getting buzzing or dead notes, look carefully to see what the problem is. Fix it, then move on to adding the next finger until you have the complete chord.
This method will work, but it takes time. Keep your practice time short on barre chords, don't get frustrated. Your body & muscle memory need time to catch up to what your brain is asking for... you'll get there, and eventually it will seem way easier than it is now.