Help! on dating!?

I've been seeing my crush for over a month now, he's very sweet, he always sends me goodmorning texts, he takes me out, he always wants to see me, and when I went on vacation he texted me every single day and even picked me up from the airport. Anyways.. his ex lurks on both of us. And she throws ALOT of shade. I don't know her, but I know they dated. Whenever he tweets about me she likes them. She had even liked my tweets about him even though we don't follow each other. What bothers me the most is that he still follows her and he likes her stuff too... it makes me wonder and overthink. Help :(