I'll start with the lack of blooming first as I think it's easier to answer. Being in north-facing windows probably provides too little light for the plant to bloom well. In general, violets do best in unshaded east windows (except for the height of summer in southern areas), or west or south facing windows with some sheer curtains or the like between them and the windows. A little more light and I think you'll see much improvement in blooming.

As for the long stem, they happen with age and aren't really a concern for the plant health-wise, but the can be aesthetically unpleasing. If it doesn't bother you, I wouldn't worry about it. I've heard of plants being coiled up a couple times in their pot and they were healthy.

If the long stem (what we call a "neck") bothers you, the situation can be rectified, though the solution is a bit drastic. If you're really attached to the plant I would recommend starting leaves from it and waiting until you have strong plantlets before attempting the following procedure.

1- Take the plant out of the pot.
2- Remove all but the 5 or 6 leaves nearest the top of the plant.
3- Cut the neck off leaving 1" of stem below the lowest leaves.
4- Using the back of the knife, scrape the scaly material off the neck until it is green and juicy.
5- Fill a pot with new potting mix and insert the prepped plant until the stems of the lowest leaves are just at the potting mix level.
6- Water well.
7- Place a clear ziploc bag over the plant and pot to keep humidity in. Because the plant has no roots at this time this is important so that the leaves don't dry out.
8- In a month or so give the plant a light tug. It may be rooted by then. If not, replace the bag and wait a couple weeks more. Repeat.
9. Once the plant is rooted, be sure to harden it off. It has been in a humid environment and a quick adjustment to room conditions could kill or harm it. Cut 1 upper corner off the bag and be sure it allows room air in. Wait a week and cut the other corner off. Wait another week and cut the top completely, but leave a sleeve of plastic around the plant for a few days before removing it completely.

This approach may sound drastic, and it is. If you feel scared or overwhelmed to do it, you may want to seek out guidance from a local violet club or experienced grower to help you. And remember to start those leaves and have plantlets as an insurance policy just in case...

Hope this helps,
Mark