I bf, expressed, mixed fed and moved fully to formula when dd was 10 months.
As far as I am concerned, and many many people I know feel the same way - However you feed your DBaby, it is best because baby is getting fed. If you bf, that's great in terms of giving DBaby extra immunity etc. BUT, it doesn't matter in the grand scheme of things how long you manage to bf for - it is difficult, there can be problems like mastitis/issues with supply/baby can't latch etc, quite apart from the hassle for DM with diet and dealing with leaks etc.
For some, it really is just "plug in and feed", but for many it's not.
Formula is also not as straightforward with sterilising, boiling and cooling water, storage when travelling etc.
What I mean is that there are pros and cons to each. And primarily it is the choice of the DM, and only HER, how long bf'ing will last.
So well done for managing 2 months, that is a really good start for DBaby. A lot more than many who really want to bf have been able to manage. And it sounds like you are ready to move to another new phase in caring for your DBaby and helping her grow big, strong and healthy overall.