Easy fold at the end, villain is aggressive and solid player. Any thoughts besides "fold pf"?

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $0.25/$0.50
6 players
Converter

Stack sizes:
UTG: $51.20
UTG+1: $50.10
CO: $48.55
Button: $31.85
Hero: $108.85
BB: $50

Pre-flop: (6 players) Hero is SB with 8 A
2 folds, CO raises to $1.5, Button folds, Hero calls, BB folds.

Flop: A 3 9 ($3.5, 2 players)
Hero checks, CO bets $2, Hero raises to $6, CO calls.

Turn: 4 ($15.5, 2 players)
Hero bets $10, CO raises all-in $41.05, Hero folds.