How can I prevent my previous relationship from ruining my current one?

I broke up with my ex July of last year after finding out that, not only had he been cheating on me with someone I worked with, but he was also married to another woman!! I cut all ties with him, blocked him from my life and haven’t talked to him since. I’ve had absolutely zero feelings left for him since shortly after breaking things off. Since then, I haven’t wanted to get involved with anyone and have been enjoying the single life for the past year.

That is, until a few weeks ago, when I met the most wonderful guy I’ve ever had the pleasure of meeting. I’ll try not to gush too much, but he truly is an amazing person and makes me feel like the luckiest girl in the world. With him, things are just easy. I don’t feel like I’m walking on eggshells and I never have to wonder what he really means by what he says.

The one thing that’s been bugging me though is that, when I’m not with him, I keep getting flashbacks of my previous relationship and they make me so anxious that I have to cry in order to get some relief from my anxiety. This really irritates me because I’m a really confident and overall happy person and hardly ever get emotional/cry. I know that he’s nothing like my ex, but at times I can’t help feeling anxious.

What can I possibly do to make my anxiety go away? Could it be that I have “relationship PTSD”? (Is that even a thing?) Any other advice in regards to this situation?

Thanks in advance! Your help will be greatly appreciated!