Here\'s a workflow that I commonly deal with at work.
git checkout -b feature_branch
# Do some development
git add .
git commit
git push origin feature_branch
>
In this particular case it seems you "know" that only the squashed work of the branch you originally worked on has been put into master.
So you can happily merge by keeping your changes every time when there is a conflict. There is an option for that:
git merge -Xours master
See https://git-scm.com/docs/git-rebase for details more details.