You may always have the mixed emotions, so to start, I would not expect myself to just let that go, or get over it, as you might feel you should. You can grieve the loss of not being "able" to just naturally get pregnant the old fashioned way. It is a loss, and trust me, as someone who is starting IVF #2 this week, you should mourn it as such. You may feel that your body failed you, that you read all the time about 'older" women in their late 30s/early 40s just magically getting pregnant. The reality is that a LOT of women use some sort of infertility treatment, they just don't talk about it because there is a stigma and shame attached.
Now the good news - IVF (if that is the route you go, though your doctor will probably try IUIs first) is NOT the horror show some may lead you to believe. Sure, it is tiring and you have to do some part of it daily, whether it's injections, blood work, ultrasound, or all three. It is mentally very tiring as well, trying to keep your spirits up and stay positive and focused on why you are doing it in the first place. But it's not as awful as you might think, it goes by very quickly, and it's exciting in a way, because science really does have such amazing advances that allow us to fulfill our dreams! If you have a good doctor/clinic, chances are the nurses are awesome, and you are all in it together with eyes on the prize. It does go by fast. I would never be doing it again if this wasn't the case.
Just remember that although you may not resolve the conflicted feelings, you will get through this, and when that baby does arrive, you will NOT care how s/he was conceived. You will be a much stronger woman and a better mother for all of this, please believe me. Don't be afraid to talk to trusted friends or a counselor if you think you might benefit. Good luck!! You can do it!!