Yes, it's a tall order, mate, like many have said. In running, progress starts out as a monsoon for beginners. Over time, that "monsoon of gains" slows to a trickle as you progress. Keep that in mind.
But there's nothing so inspiring as a valiant effort and I thought this was a thread about someone trying to give it their all, not a b*tch and moan session for the negative nellies.
Here's what I'd have you do.
For the next two months, build mileage up to about 55mpw average, the goal being ultimately to do a HM TT around late July. Those two months would consist of three workouts per week--one day for speed, one day for threshold/hills and one longish run (12-15 miles). The rest easy, with strides two times/week after the easy run. (By the way, do you have hills nearby?)
After the HM TT, i'd reassess and start introducing a bit more Marathon specific pacing, while keeping in speed, threshold and hills. More emphasis on endurance, less on speed. I'd probably have you cut down from three workouts to two/week--Daniels-esque approach where the two sessions are longer and contain a mix of threshold and MP. Mileage would build to 65-70MPW average, with a sprinkling of down weeks to give your body some time to rest.
Those are my two cents.