Im not getting bored with my running but i wouldnt mind a little more variety. What are your interval running routines? Have you got a routine that works for you whether it be sprints, long distance, intervals, tabata or any other variations. I usually run 10km a vary up the speeds depending on how i feel.
Once a week i used to run 1 mile hard and fast 6-8 mins then walk for 2 mins then do the same twice over ,try and do the miles in the same time, REST OF MY RUNS WERE LONGER AND SLOWER BUT ALWAYS TRYED FOR 7-9 MINS FOR EACH MILE; or go to a running club they have great running, sprinting,intervals, routines.
..............It does indeed get boring running the same distance at the same pace all the time. To combat this, you can retain a day or two of easy-paced medium distance runs and spice up the rest of the week with perhaps a weekend long run (mileage will obviously vary depending on how much you're currently able to do) and of course speedwork.......... Go to a track and warm up with a slow jog for a mile or so. Then, do a ladder: A 200 meter run at your best mile pace (jog a 400 meter lap to recover) A 400 meter run at best mile pace (This is of course one lap of the track in the inside lane. Again, a 400 meter jog recovery after) An 800 meter run at perhaps 5-10 seconds faster than 5k pace (with another slow jog of 400 for recoevery, naturally). A 1200 meter run at same pace as the 800 (take an extra jog lap to recover if you need it here). Lastly, do a 1600 meter at 5k pace. Be sure to cool down for a lap afterward, and don't forget to stretch. Then when you get good at that, you can play around with the distances of the intervals if you like, or maybe do a "pyramid," which is like a ladder, but after moving up the ladder, you go back down it again. Those are killers.