I was in a very similar situation four years ago and my advice is give it some time. You have been dealt a tremendous blow. Like many others said you are suffering a great loss and you both need time to process. I too put up walls and this was the biggest mistake I have made in my life. By shutting out people and not allowing myself to grieve led to my marriage falling apart. Luckily we got into therapy and were able to work through things and our marriage is stronger than before. I felt that it was all my fault and that I was the only one who had the right to grieve, but I was wrong. My husband was grieving too, he was grieving the loss of our biological child. I didn't consider his feelings and I regret that to this day.
My sister too offered her eggs and all I can advise is again take some time and please get some counseling for all four of you. There are a lot of issues I would never have thought of that could arise. Because of this I know several clinics that won't even use known donors. I know it sounds like a great alternative, but you really need to consider how you will feel in certain situations and will those feeling jeopordize you and your sister's relationship.
We wound up choosing an anon donor and are now pregnant with twins. It has been a long journey with many twists and turns, but in a way I feel so thankful for each lesson I've learned along the way and I know these babies were meant to be our babies.