Op - I really really feel for you on this. I have just got back from a mammoth shop with DS who heads off to uni on 17th. Despite still having DD16 (& DH) at home, I know I am going to miss him desperately. This morning was bittersweet to say the least. It was lovely to spend the time with him, and revel in what a lovely young man he is, but boy was I sad too!!
He is mature and confident, and done most of form filling etc himself, but has involved us all the way, which has been lovely (esp as we will be paying for lots as he will only get minimum loan). I had to accept and pay deposit for his accommodation 2 weeks ago as he was on DoE with no internet - Luckily he got first choice of halls so I didnt have to make any decisions.
I am also in my fifites, so have the menopause to deal with too, plus lost my mum 6 months ago, so now have lots of spare time after spending almost 2 yrs supporting her from a distance then sorting estate and house sale. I know I need to find something to fill the 2 days I have off work, esp as DD going to college and will be later home than school.
I hope your DS changes his mind about you taking him, I guess Oxford is all catered, but will he need to take bedding etc. surely that wont be easy on train? There is no way my DS could go on train with what we have bought today, but then he has bedding, cooking stuff etc. Fortunately he is more than happy for us to take him although I guess he will also be glad to get rid of us once car unpacked.
He is also only an hour from home and 45mins on train, and DH and I both work between home and Uni, so can be with him in 30 mins from work if he needs anything. I can see us having some Saturday visits to his Uni city, meeting him for lunch! It is also his birthday this term, so he will either come home for a day or 2 or we will go and take him out.
Try and stay positive, remembering everything you have done to help him get to such a prestigious Uni. The short term will be over in no time and I guess he will appreciate you more when he has been away a while.