Don't know what to do? Help!

I am a divorced and just recently this married guy going through a divorce contacted me and at first I thought it was just a casual thing but now I am stating to feel uncomfortable because I'm not sure what his real intentions are towards me! He has only been separated for 4 months and he is still legally married I honestly feel bad talking to him right now! Should I just stop answering his messages or should I tell him we shouldn't talk anymore?? Don't know what to do?