Even for those with small mouths it should still work 99% of the time if you just gently but confidently open their mouth with your hands, tilt the head up, and drop the pills right into the far back, then close their mouth and hold it closed.  Some dogs will just  swallow, others will then need you to gently rub their throat, which typically triggers a swallowing reflex.  And don't let her open her mouth till you've seen her swallow.  Then it's time for a treat so she doesn't think it's a punishment.  That's always worked for me.

I would absolutely not worry about addiction  - you'd need something MUCH stronger than tramadol for a couple weeks to do that!  Tramadol is a synthetic narcotic made by design for humans alergic to stronger narcotics - and a parallel desire to have a mild narcotic that is not habit forming/adictive. 

But in the worst case scenario if you do at some point have a hard time ramping off the pain killers one thing that I have observed to work is a good 15 minute doggie acupuncture session.  Tell the vet accupuncturist the issue and they'll know exactly what to do right away.  It honestly is excellent at relieving pain and anxiety/other symptoms related to narcotics withdrawal.   

The accupuncture suggestion is a product of my first-hand observation of my GSD Zuni's response to 2 recent accupuncture sessions.  Yes, she's seeing an oncologist and we're going with amputation and carboplatin but we are also seeing a board certified vet naturopath.  It was the naturopath's suggestion and I had NO prior experience with it but thought why not.  I was shocked to see how well it worked on Zuni - particularly since you can forget the placebo effect being a factor with dogs (I think).