I exclusively pumped for 6 months, stopped last we and was shocked at how fast stopping is(!) literally did my last express Monday morning and only had to do 5 short bursts to give some relief in the evening and on Tuesday.
It is totally possible, I tried to breast feed for a week, but I got myself in such a state that for my own mental health had to stop. DH and I went and got a pump, I expressed for the first 2 months on a schedule of 20 minutes each breast after I had fed him. I found pumping after a feed helped with my supply as he was near me and got "the juices flowing" to put it crudely.
Month 3 I settled into a schedule of 5 times a day half an hour each side.
Month 5 I reduced that to 4 times a day.
And then in the 3 weeks leading up to me stopping I reduced it to once in the morning and once in the evening 15 minutes each side.
I found when cutting down on my express sessions, (obviously) my supply slowed down, so while I was still managing to express between 2 and 3 feeds each time, I had to introduce formula to ensure I had enough milk for him.
It is possible and I have already decided that I will exclusively express for the next baby when we decide to have another.
The only thing I would do differently and encourage anyone who is planning to express to feed, invest in an electric pump, I did it all with a medela harmony which is a manual pump, I have calluses on my index fingers and rsi in my thumbs... Not recommended!!!!