From Last to Firts by Charlie Speding, it really helped me back from injury and low motivation. It's not a how to train book more of a motivational story about his highs and lows of running and how he came through them.
I've had a similar problem for the past 3 years, used to do 5:30 - 6:30mmile dependant on distance then with injuries I lost my motivation and only seemed to be able to do 7/ 8 pace. A good book my coach recommended was From Last to First by Charlie Speding, ( other books avaliable) a good read and helpful. My motivation and speed is coming back now but I have changed my distance and this seems to have helped. May be you need to try different training sessions and race distances so your not comparing yourself to the way you used to run. Swimming has helped my fitness and kept running down to reduce the risk of injury. Hope this helps, the best advice is just go with it, it'll come back when your not trying.
You could just need a rest and to take it easy for a week or so, even if you don't feel tiered if your body is it wont let you do it no matter how hard you try. If your stressing about hitting the speed each time you run now you'll find it harder, try jogging 5 mins and if you feel ok increse the speed every 3 / 5 mins untill you hit your normal pace. It'll come back when your not even trying- I keep getting injured, if I relax and jogg my speed brings its self back with the help of a few sprint sessions. If I get p* and try to push each one nothing happens and I get slower.
Don't give up running is done with the mind not the legs!
Skyrac has changed it's website, its now up and running again www.skyrac.co.uk. We take adults to children. We have social runners and competitive runners running Track, Cross Country, Fell, Road, Trail, Fun Runs. We Train at Nunroyd Club House Tuesday and Thursdays from 7.30 (not the pub sorry to disappoint) You can either go out for a run or do some coached speed sessions on the park (would be best to wear spikes or trail shoes). The coached sessions have a wide age range from juniors (in a separate group) to 20, 30, 40, 50, 60+. We enter athletes in the couty championships as well as local races. We also train at Carniegie Monday and Wednesday check out the website if you want to have a go. Also a Dragon so would recomed them too! Although most of the clubs in the area are quiet good, just depends on what your looking for? And of course the vest colours you like (maybe just a girl thing)