Is it okay to ignore text messages?

How does everyone feel about this?

I always feel bad and typically never do this, but recently started ignoring a f boy and it’s really helped me.

Here’s more of what brings up this question to me:

I also just got a text from someone I went to college with 4 years ago and he randomly hits me up so I don’t consider him a friend. In that time frame, we’ve probably had contact a handfull of times. It makes me uncomfortable because I’m a very private person. I don’t want to catch up with someone who isn’t part of my life that would ask about if I still work at the same place etc. I feel he’s always used me in the past to help him sort through his girl issues and one time he even tried to convince me to hang out with his now ex gf by kissing up basically. Is it okay to ignore this person?