How long are you gone usually? He'll be fine if you're gone for a few hours or so. Just be sure to have plenty of toys in his cage for him to play with. Also, it might help to leave a radio on, tuned to soft music.
If you want him to be really close and bond with you, then don't get another parakeet. Otherwise, he'll just end up bonding with the other bird and he won't pay any attention to you! I have one parakeet, Chipper, and he's doing perfectly fine by himself. I give him a lot of attention though. I leave the house for around 2-3 hours usually, and he's fine.