"If it weren't for your serves, I'd have won." How many times have you heard or said or thought that? Receive is seemingly everyone's weakness. But it shouldn't. The primary reason why so many people have weak receives is because they don't systematically practice it.
If you want to develop your forehand, you practice it. The same is true of just about any other part of your game, from serving to footwork to all the strokes. You'd practice it over and over until it's improved - that's systematic practice. But do you do the same for receive? Or do you just rely on practicing it in game situations, and somehow think that's all that's needed to develop one of the most difficult parts of the game?
How do you systematically practice receive? By (drum roll please) systematically practicing it. This means finding a practice partner or coach who serves to you, over and over, so you can (systematically) work on your receive. Have trouble looping a certain type of deep serve? Have your partner serve this deep serve so you can practice against it. Have trouble with a type of receive against a short serve? Have your partner serve it to you so you can practice it. The goal is to make your receive so relentlessly reliable that it not only isn't a weakness, it becomes a strength.
It doesn't matter whether your receive is aggressive (where you try to take the initiative, usually with a loop or a flip), neutral (where you nullify the server's serve and turn things into a neutral rally, in a number of ways - a consistent loop, flip, or long or short push, with the short push the most common way at higher levels), or passive (usually long pushes), it should be so relentlessly reliable that the server never gets a "free" point via you missing or popping up a ball and giving him an easy put-away. Even your "aggressive" flips should be toned down for consistency, using quickness and placement instead of overly aggressive and less consistent flips.
Once you are consistent against any given serve, have your partner or coach serve everything at you, with the intent to force mistakes. When you have a relentlessly reliable receive against all these serves, you are ready to face them in competition - and you'll never have to say, "If it weren't for your serves, I'd have won.)