Barre chords are HARD! They need quite a bit of pressure, but you need to focus on what notes you want to hear. As an aside, barre chords are what got my fretting hand tendonitis in just 6 years. Your mileage will vary.
Hey Dennis, good to hear from you, it's been awhile!
If barre chords are giving you so much trouble, something is wrong. It really does not take that much pressure at all, it is more technique than pressure. The "hitchhiking thumb" position is very important. For me, I actually have the spot of the first joint of your thumb pressing against the center of the neck. And as was mentioned earlier, the thumb points up the neck toward the headstock, not up toward the ceiling. Wearing the guitar too low
can make this difficult, so one thing you might do is experiment with wearing your guitar a little higher.
And one thing that hasn't been mentioned is setting up your guitar properly. I always take great care to set up all my guitars to my liking. Some folks are afraid of this, but it is not difficult, and the only way you learn is by trying it for yourself. For me, I love super-low action. I will make the action as low as possible without string buzz. First, I usually tighten the truss rod. I try to straighten out the neck as much as possible. This will bring the strings down very low. This will throw off your intonation, so then I carefully adjust the saddles so that a fretted note at the 12th fret perfectly matches the open string. Another nice thing about low action is that the notes are not caused to go sharp as they will do with high action. Then I will slowly lower the saddles and play up and down the neck on a string with normal picking force and listen for string buzz. When I finally hear a trace of buzz I will raise the string just enough to eliminate the buzz. I go through each string like this.
When I am finished I have super-low action without fret buzz whatsoever. I can easily play barres up high above the 12th fret without hardly any force whatsoever. It is so easy I almost just place my fingers on the strings.
Now this is me, some folks do not like super low action like this. But I love it and it absolutely makes playing barre chords much simpler and easier.
I would encourage anyone to learn how to set up their own guitar like this, but if not, take it to your local shop for a good setup. Makes a world of difference.
If you know something better than Rock and Roll, I'd like to hear it - Jerry Lee Lewis