Relationship advice! Should I keep trying?

Hello everyone! I need some advice and all opinions are welcome! I’ve been with my partner for almost 5 years now, and our relationship has been great, but I’m starting to get, for the lack of better word, bored with our relationship. It’s very stressful as well, because I feel like there is no future with him. In the past, (about 2 years ago) I thought this as well and tried to break it off, but he asked me to give him another chance and I did. He also wants to keep or relationship a secret, so for 5 years no one in his or my family even know we’re dating. I’ve spoken to him about these feelings and concerns of mine before, but he always seems to avoid it. And he has actually told me before he doesn’t like thinking of those things because it makes him upset. And lately I’ve started feeling attracted to other people as well. I just don’t know what to do and would really love some advice.