Kerrigan90 I am so sorry that you have found out this sad information for yourself and your husband. I don't want to pry but have you been told by a fertility clinic that you will not get pregnant with your own eggs or do you not have eggs (no need to reply I am just thinking out loud.).
We are not yet adoptive parents but are parents to a DD aged 8 born from IUI fertility treatment. I was told by a clinic years ago we would never have another child with my own eggs. Despite this I did try treatment with my own eggs (which failed) and eventually treatment with donor eggs, which also failed.
I think fertility treatment (even with donor eggs) is very different from adoption. It does take a while to get used to the idea that the child will not be genetically linked to you if you mother a child with a donor egg, although they would biologically linked as you would carry the baby and give birth. I think one question is how important the whole pregnancy and birth thing is, and for some people it is very important, for some not so much. For me it was not so much of an issue but I must admit I did still want to attempt treatment with donor eggs.
In the UK the donor is annoymous, unless it is a friend or relative of course, and the child has the opportunity to trace the donor who donated the egg. For this reason we chose to have treatment in the UK, because we felt it was better for the child to have the chance to know who the donor was when they were older. In some other countries it is not something that a child born of donor eggs has the right to do.
I know three children born from donor eggs in real life, and their mothers think of them (rightly) fully as their children. I also speak to people on line who are going through treatment/have children by donor eggs, and they are also very comfortable with the process. So I don't think for me or for others in general who have treatment with donor eggs that there is any sense of their children not being their own. All the people I know of went with anonymous donors. I don't know anyone who had a donor they knew.
Personally, I do not think there is any sense that if I were not to get pregnant naturally that in any way that was 'meant to be'. I tried very hard to get pregnant many times, once I got lucky and it worked with my own egg, and many times with my eggs and donor eggs it did not.
There may be threads on here under fertility and assisted conception on this.
As far as adoption goes I will let others wiser than I am answer your questions. My husband and I decided to give up on fertility treatment after our money ran out. I don't really regret doing it; I wanted to do it and was lucky enough to be able to do it. It didn't work. But for many others it does. I have wanted to adopt for about 20 years and now seems the right time. I think my head is in a better place than when I was in the middle of all the treatment. I think adoption is very different thing to fertility treatment but I know there are some on here who have experienced both so should be able to tell you more.
You can't pursue adoption and treatment at the same time, at least you can't in my area. I think it would be very hard/impossible to be having treatment and putting your mind into adoption and all that entails.
All best wishes with whatever course you pursue and whatever you do, please do get lots of support in real life (and on here) to help you with deal with this very sad news about your own fertility. However things work out, you will need to grieve for this and get support.
All the best.