Breeding is a whole other animal, lol...
Like DT said, a bubble nest means the betta is happy and healthy, and his instinct is to build a bubble nest. No need to remove it. An ill male will probably not make a bubble nest. I have never had a female betta and my male bettas have always built bubble nests. I used to "save" the bubbles before a water change by using a spoon to put them in a little plastic cup, and after the water change I would put them back. You don't need to do that...the betta will rebuild after a water change if he wants to. I used to love sitting nearby and hearing "click, click" as they blow their nests. I did notice that after about 8-10 months, as they got a little older, they stopped making the nests.