I bought it end of July. They've been out since I bought it so a bit I'd think. Any idea why the petals would look like that?

The major damage on one flower could be mechanical. (touching blooms etc. happens at orchid shows when the general public test them to see if they are real, not plastic). Perhaps you have sprayed the flowers during watering episodes and fungus spores have got in.

Just guessing!. Maybe something in the conditions where you have the plant. More guessing!

Really do not know how long they last in good conditions. The one in this room has been to two orchid society monthly meetings and spent 4 days in the arid air at an orchid show in a shopping centre and the flowers are still fine. Sorry not much help.

Do you think it might have something to do with direct sunlight? I'm wondering even though a pillar blocks the sun that it might still be too much. Thoughts?

Conditions are a description of where you have the plant. Did you buy the plant just for the blooms or do you wish to keep it long term in the hope of it flowering again?

Technical. Conditions at 12:30pm latitude 33S Temperature near in-bloom plant 23.1C

Humidity 58%.Near North facing window. Light filtered by matchstick blind. Sun is in the "wrong" place in the sky, Southern Hemisphere. Plant got sunlight filtered by the matchstick blind during winter.

American Orchid Society Phalaenopsis notes

I bought it for both. And it's currently sitting by a west facing window but have full windows all around the area.