Are you getting treatment for your issue Clinical Depression(suicidal tendencies are linked to depression)? If not, please try to see your psychiatrist and get on the best treatment plan you can so you do not have to keep suffering needlessly.
As for whether you are saved or not saved, it does not matter how long you have been saved.... what matters is that you are and you know it. So if you are not saved, it does not hurt to try again - no one is counting except you.
Now, you may wonder what Salvation guarantees you? Well, Salvation ensures that when you take your final breath in this life, rather than perish in the grave, gifted instead with eternal life, your consciousness instead sleeps in your grave until it is resurrected when Jesus Christ returns again, and thereon. Please understand that Salvation does not come with the guarantee that you will spend that eternal life you earn when you are saved in a place called Heaven - no it does not. Those who are saved(have salvation) can also end up in Hell if they refuse to obey the teachings of Jesus Christ.
As for how to get saved? According to Jesus Christ, all you do is obey a couple of commandments - believe in Him(John 3 vs 16 -21)...
16 Yes, God loved the world so much that he gave his only Son, so that everyone who believes in him would not be lost but have eternal life.
17 God sent his Son into the world. He did not send him to judge the world guilty, but to save the world through him.
18 People who believe in God’s Son are not judged guilty. But people who do not believe are already judged, because they have not believed in God’s only Son.
19 They are judged by this fact: The light[c] has come into the world. But they did not want light. They wanted darkness, because they were doing evil things.
20 Everyone who does evil hates the light. They will not come to the light, because the light will show all the bad things they have done.
21 But anyone who follows the true way comes to the light. Then the light will show that whatever they have done was done through God.
..., partake of the Last supper(John 6 vs 47-57)
47 “I can assure you that anyone who believes has eternal life.
48 I am the bread that gives life.
49 Your ancestors ate the manna God gave them in the desert, but it didn’t keep them from dying.
50 Here is the bread that comes down from heaven. Whoever eats this bread will never die.
51 I am the living bread that came down from heaven. Whoever eats this bread will live forever. This bread is my body. I will give my body so that the people in the world can have life.”
52 Then the Jews began to argue among themselves. They said, “How can this man give us his body to eat?”
53 Jesus said, “Believe me when I say that you must eat the body of the Son of Man, and you must drink his blood. If you don’t do this, you have no real life.
54 Those who eat my body and drink my blood have eternal life. I will raise them up on the last day.
55 My body is true food, and my blood is true drink.
56 Those who eat my body and drink my blood live in me, and I live in them.
57 “The Father sent me. He lives, and I live because of him. So everyone who eats me will live because of me.
58 I am not like the bread that your ancestors ate. They ate that bread, but they still died. I am the bread that came down from heaven. Whoever eats this bread will live forever.”
.... and be baptized (Mark 16 vs 15 -16)
15 He said to them, “Go everywhere in the world. Tell the Good News to everyone.
16 Whoever believes and is baptized will be saved. But those who do not believe will be judged guilty.
After you have done all of the above with a willing heart, you are indeed saved. What you want to do next is consider continuing in your obedience to the commandments of Jesus Christ as that is the only way to enter into the Kingdom of Heaven and live a sin-free life.
The teaching of Jesus Christ, the New Covenant agreement are found recorded only in the 4 Gospels, and there are some key commandments that I would suggest you begin to obey as soon as you are sure you are saved. These commandments are so you can become worthy of becoming a follower of Jesus Christ - Jesus Christ abides in those who abide in Him(i.e. accept and obey His teachings) and these are commandments to become worthy of Him.
Matthew 6 vs 25 -34
25 “So I tell you, don’t worry about the things you need to live—what you will eat, drink, or wear. Life is more important than food, and the body is more important than what you put on it.
26 Look at the birds. They don’t plant, harvest, or save food in barns, but your heavenly Father feeds them. Don’t you know you are worth much more than they are?
27 You cannot add any time to your life by worrying about it.
28 “And why do you worry about clothes? Look at the wildflowers in the field. See how they grow. They don’t work or make clothes for themselves.
29 But I tell you that even Solomon, the great and rich king, was not dressed as beautifully as one of these flowers.
30 If God makes what grows in the field so beautiful, what do you think he will do for you? It’s just grass—one day it’s alive, and the next day someone throws it into a fire. But God cares enough to make it beautiful. Surely he will do much more for you. Your faith is so small!
31 “Don’t worry and say, ‘What will we eat?’ or ‘What will we drink?’ or ‘What will we wear?’
32 That’s what those people who don’t know God are always thinking about. Don’t worry, because your Father in heaven knows that you need all these things.
33 What you should want most is God’s kingdom and doing what he wants you to do. Then he will give you all these other things you need.
34 So don’t worry about tomorrow. Each day has enough trouble of its own. Tomorrow will have its own worries.
Matthew 10 vs 34 -37
34 “Do not think that I have come to bring peace to the earth. I have not come to bring peace, but a sword.
35 For I have come to set a man against his father, and a daughter against her mother, and a daughter-in-law against her mother-in-law.
36 And a person's enemies will be those of his own household.
37 Whoever loves father or mother more than me is not worthy of me, and whoever loves son or daughter more than me is not worthy of me.
38 And whoever does not take his cross and follow me is not worthy of me.
39 Whoever finds his life will lose it, and whoever loses his life for my sake will find it.
Matthew 18 vs 3 -4
3 Then he said, “The truth is, you must change your thinking and become like little children. If you don’t do this, you will never enter God’s kingdom.
4 The greatest person in God’s kingdom is the one who makes himself humble like this child.
Matthew 16 vs 24-27
24 Then Jesus said to his followers, “If any of you want to be my follower, you must stop thinking about yourself and what you want. You must be willing to carry the cross that is given to you for following me.
25 Any of you who try to save the life you have will lose it. But you who give up your life for me will find true life.
26 It is worth nothing for you to have the whole world if you yourself are lost. You could never pay enough to buy back your life.
27 The Son of Man will come again with his Father’s glory and with his angels. And he will reward everyone for what they have done.
28 Believe me when I say that there are some people standing here who will see the Son of Man coming with his kingdom before they die.”
Read through the Gospels as if you were reading a novel even, so you can get a better understanding of the person of Jesus Christ, His teachings and the many commandments available for you in Him. There are about 46 commandments in total included in the New Covenant, Jesus Christ.
