Head over heels

I divorced my ex 3 years ago after he cheated on me. In June I took the plunge and joined a dating app. I matched an amazing man, texting and calling everyday - we met a month later and it was as if we'd known each other all our lives! We had a long distance relationship and tried to see each other once a month. His mum was diagnosed with cancer during this time which was tough but brought us closer together. I fell head over heels for him - we spoke often about marriage and the future due to our faith. We spent a weekend at the coast together which was bliss. After that, contact started to reduce - he said his mum was starting chemo. Something didn't feel right but I didn't want him to think I was needy. We last met a month ago, his lack of communication was making me worry so I offered him a break but he didn't want that and said he wanted to marry me next summer. After that I didn't hear from him for 2 weeks and out of the blue got a call to say he was in Dubai! I thought it was irresponsible but told him to enjoy himself. And he did...he has been following and liking lots of girls on Instagram (without responding to my follow request). Worst of all, he has reactivated his dating profile. I text him two days ago, no response. It really, really hurts - I feel so stupid.