"Permission denied (publickey)" every time I try to push to git
I think this happen because when you generated your ssh key, you entered a passphrase for security. When you start the ssh-agent and add ssh/rsa_id it should as for the passphrase.

[root@user xxxxx]# eval "$(ssh-agent -s)"
Agent pid 12082
[root@user xxxxx]# ssh-add /home/user/.ssh/id_rsa
Enter passphrase for /home/user/.ssh/id_rsa:
Identity added: /home/user/.ssh/id_rsa (/home/user/.ssh/id_rsa)

git push -u origin master
Counting objects: 94, done.