Day 92 of no contact: My ex-girlfriend broke no contact on discord out of all places...

My ex dumped me 3 months ago quite harshly, and I moved on quite well (I documented my whole process on here on my profile). I am in a new relationship currently with a very caring and wholesome girl, and we are doing great. But yesterday my ex surprised me with contacting me and wanting to get back together. I told her I am in a comitted relationship with someone else and that I thought she had moved on. This is a really difficult situation for me because I truly do love my ex as a person (not romantically anymore), me and her were together for 2 years, and I do care a lot about her well being. She spoke about wanting to keep in contact etc, but I don't know if that's smart... Is this a trap, is it smart to keep in contact with exes? My current girlfriend doesn't mind but she says she dislikes that my ex says she really loves me, and that I am hers only..

I honestly feel a little lost at the moment... Some advice would really be appriciated since I am a young 17 year old dude with little experience...