The French defender was absent for the majority of last season as he underwent treatment for cancer and was eventually released at the end of the campaign.
The 33-year-old joined the newly-promoted Ligue 1 side and claimed that he has no ill feeling towards Barca for the way he was moved on at Camp Nou.
"I support the people I love and I call them. I'm still very attached to Barcelona. But I don't regret leaving the club," Abidal told RMC.
"We worked together for six years. I sent messages to my colleagues to wish them good luck with the match [against Atletico Madrid].
"I'm very happy at Monaco. I can't say anything negative about Barcelona. I was expecting a new contract but it never arrived. It wasn't an easy choice for Barca."
Abidal made his return to the Barcelona side in April.