A Labral tear can be diagnosed with an MRA ( MRI with a contrast dye) has this been suggested to you? Also I would ask your OS if they have ruled out FAI as this can be an underlying factor to a tear and often causes the posterior symptoms that you describe. No amount of PT will cure a labral tear, it would need an arthroscopy.
Good luck I hope you find an answer soon, after 5 years of dealing with complicated hips and 6 surgeries I know how frustrating it is.
I'm using the My Asics for the GNR in September, my first half. I like the plan, its pretty straightforward to follow and you can set the amount of days you want to run or alter the days if needed. I set the finish date for 2 weeks before though, just in case I need to miss a week for any reason and also because the plan only takes you to 11 miles and if I have a spare week at the end before the taper I would like to do a 12 miler just to get a bit closer to the actual race distance.
I had that problem when I started a year ago, but it did improve as I got fitter. I still experience it occasionally if I increase my pace or sometimes in the first mile until I get warmed up properly. I find slowing my pace or taking a walking break until I can get my breathing under control works then I can finish the run.
I can never decide whether an inhaler would help or whether is just lack of fitness but it has definitely got better so I'm presuming its the latter for me
I'm running the GNR as my first half marathon too-can't wait!
I think there is about 20 weeks to go, which will give you 8 weeks to do the C25k then there are beginner half plans (icklemicheals link look good) , that take you from 5k through to race day over 12 weeks which should work out barring anything unforeseen.
I'm still very much a beginner too, but the best advice I was given was to run as slow as needed to complete the planned time/distance and you will find you gradually get quicker as you get more miles under your belt. I was so self-conscious at first so used to run at 5am to avoid being seen-now I don't care. I figure those who run won't laugh because they know how hard it is, and had to start at some point themselves and those who don't run couldn't do it anyway so aren't worth bothering about!
Good luck, have fun and let us know how you progress. See you at the finish
Have you considered getting your hips checked out by a consultant that specialises in young people (under 50ish) with hip problems. In 2008 my hip xrays were also considered normal -since then I found the right consultant who, knowing what to look for, diagnosed severe hip dysplasia! After 5 surgeries, including 2 reconstructions of my hip sockets I get the final lot of metalwork removed in April then can continue my training for the GNR. Unfortunately my story isnt unique and I know of many others who were also told by consultants that their xrays were normal too.
Regarding the VLM only you can decide but if you are able to do it without causing too much pain but I am sure you wont be the only one walking it and positive noone will laugh-everyone has their own reasons for taking part and various limitations that mean some cant run it.