Confused and uncertain

I have dated a guy for just over a year (let’s call him Max). Max and I had a great relationship and never had a single disagreement until a few weeks ago and we got in two arguements in just two weeks. I have many issues with Max that I’ve talked to him about before: the issues include his clingyness, lack of his own friends, and sometimes present immaturity. Despite all this I do love him. I started hanging out with another guy, “Derek,” and though we appear very differently, we’re a lot alike and I enjoy spending time with him. I broke up with Max because I told him it was unfair for me to be in a relationship with him if I have feelings for Derek. Max told me that he’s very set on making things work and working on the above listed issues. The thing is, why did it take me breaking up with him to realize that I was serious when I would speak about what was bothering me? I am very attached to Max and we have a lot of history. I do, however, have feelings for Derek. I’m torn between two great guys. One I have history and comfort with and one is new and exciting. Both care about me so much and I don’t want to lose either, but I know I need to make a decision. Any advice?