Should I?

Me and my ex have been broken up for 7 months. We haven't talked in 5 months, back when he sent me long messages apologizing for not being a very good boyfriend and wishing me well and everything and I never responded to him. I feel like I should message him just asking how he's doing? We were together for 2 years and lived together. I am in a relationship with another guy and we're not in love, not like how me and my ex use to be. I'm not wanting to get back with my ex I just genuinly care how he's doing. So should I?