How about 2 - 3 months. None that I have purchased have lasted 6 months.
I don't know why yours are not lasting that long. I have some that have lasted a really long time in a light light fixture that is on at least 8 hours a day. I can't tell you exactly how long but if it wasn't a lot longer than the incandescent ones I wouldn't bother. The one fixture in question has 5 bulbs in it. That is 5 60 bulbs I used to use to 5 14 watt ones now. 300 watts to 70 watts. Plus I don't have to change them as much in that fixture. But for the rest of my house I use the old bulbs since they are not on as much.
But I have to say this is a stupid law by congress. They didn't have to ban these bulbs to get people to use them. All they had to do is let you write them off and they would have gotten a lot of people to switch on their own. But they will lose money doing that from the write off. Now with a ban coming they will get more tax dollars since these bulbs cost more. Funny how that works. You don't think they thought about that before they did this law do you? ;)