when is it time to leave a relationship?

me and my boyfriend will be together 3 years in November. we are only 16. i love him a lot, he’s all i really have and i want to be with him and have a future with him but i’m in constant fear of him leaving me. he’s left me before multiple times for a short period of time to figure out what he wants and to figure out his feelings. i overthink a lot and every slight difference in his actions or anything i get anxiety and think he’s ending the relationship soon for example, a couple days ago he took off our highlight on his page that had all of our pictures on it and it was really important to me. i talked to him about it and he told me “i just wanted to see how long it took you to notice it was gone, it’s been two weeks i’m surprised it took this long for you to notice…” i told him it was important to me and i don’t really check peoples profiles often, i use instagram mainly to store my pictures. he asked me why it was important to me and i told him it gives me reassurance that you want to be with me and you want others to know about us. (note: last time he took our highlight off he broke up with me a week later) he told me i was overthinking which made me a little upset, anyways he sent me a screenshot of it being back on his profile but it’s been a week now and it’s not showing up on there on my phone so i can’t seem to believe that he actually put it back up. i have trust issues due to him lying often in our relationship especially in the past. so with me always worrying about him leaving me, not being able to trust him, is it time for me to leave even though i love him and want to be with him?